diff --git a/android_webview/browser/net/aw_network_delegate.cc b/android_webview/browser/net/aw_network_delegate.cc
index 0c21d063c38415..bd69d38531196f 100644
--- a/android_webview/browser/net/aw_network_delegate.cc
+++ b/android_webview/browser/net/aw_network_delegate.cc
@@ -87,7 +87,7 @@ bool AwNetworkDelegate::OnCanSetCookie(const net::URLRequest& request,
 }
 
 bool AwNetworkDelegate::OnCanAccessFile(const net::URLRequest& request,
-                                        const FilePath& path) const {
+                                        const base::FilePath& path) const {
   return true;
 }
 
diff --git a/android_webview/browser/net/aw_network_delegate.h b/android_webview/browser/net/aw_network_delegate.h
index 281026d057b166..de1af58f94c9c0 100644
--- a/android_webview/browser/net/aw_network_delegate.h
+++ b/android_webview/browser/net/aw_network_delegate.h
@@ -52,7 +52,7 @@ class AwNetworkDelegate : public net::NetworkDelegate {
                               const std::string& cookie_line,
                               net::CookieOptions* options) OVERRIDE;
   virtual bool OnCanAccessFile(const net::URLRequest& request,
-                               const FilePath& path) const OVERRIDE;
+                               const base::FilePath& path) const OVERRIDE;
   virtual bool OnCanThrottleRequest(
       const net::URLRequest& request) const OVERRIDE;
   virtual int OnBeforeSocketStreamConnect(
diff --git a/base/android/path_utils.h b/base/android/path_utils.h
index 78f02674ef8481..6c632f234cdf16 100644
--- a/base/android/path_utils.h
+++ b/base/android/path_utils.h
@@ -9,9 +9,10 @@
 
 #include "base/base_export.h"
 
+namespace base {
+
 class FilePath;
 
-namespace base {
 namespace android {
 
 // Retrieves the absolute path to the data directory of the current
diff --git a/base/command_line.h b/base/command_line.h
index 7d8627fa8417f3..aebda06fcdda1b 100644
--- a/base/command_line.h
+++ b/base/command_line.h
@@ -23,7 +23,9 @@
 #include "base/base_export.h"
 #include "build/build_config.h"
 
+namespace base {
 class FilePath;
+}
 
 class BASE_EXPORT CommandLine {
  public:
@@ -43,7 +45,7 @@ class BASE_EXPORT CommandLine {
   explicit CommandLine(NoProgram no_program);
 
   // Construct a new command line with |program| as argv[0].
-  explicit CommandLine(const FilePath& program);
+  explicit CommandLine(const base::FilePath& program);
 
   // Construct a new command line from an argument list.
   CommandLine(int argc, const CharType* const* argv);
@@ -92,8 +94,8 @@ class BASE_EXPORT CommandLine {
   const StringVector& argv() const { return argv_; }
 
   // Get and Set the program part of the command line string (the first item).
-  FilePath GetProgram() const;
-  void SetProgram(const FilePath& program);
+  base::FilePath GetProgram() const;
+  void SetProgram(const base::FilePath& program);
 
   // Returns true if this command line contains the given switch.
   // (Switch names are case-insensitive).
@@ -102,7 +104,7 @@ class BASE_EXPORT CommandLine {
   // Returns the value associated with the given switch. If the switch has no
   // value or isn't present, this method returns the empty string.
   std::string GetSwitchValueASCII(const std::string& switch_string) const;
-  FilePath GetSwitchValuePath(const std::string& switch_string) const;
+  base::FilePath GetSwitchValuePath(const std::string& switch_string) const;
   StringType GetSwitchValueNative(const std::string& switch_string) const;
 
   // Get a copy of all switches, along with their values.
@@ -111,7 +113,8 @@ class BASE_EXPORT CommandLine {
   // Append a switch [with optional value] to the command line.
   // Note: Switches will precede arguments regardless of appending order.
   void AppendSwitch(const std::string& switch_string);
-  void AppendSwitchPath(const std::string& switch_string, const FilePath& path);
+  void AppendSwitchPath(const std::string& switch_string,
+                        const base::FilePath& path);
   void AppendSwitchNative(const std::string& switch_string,
                           const StringType& value);
   void AppendSwitchASCII(const std::string& switch_string,
@@ -131,7 +134,7 @@ class BASE_EXPORT CommandLine {
   // AppendArg is primarily for ASCII; non-ASCII input is interpreted as UTF-8.
   // Note: Switches will precede arguments regardless of appending order.
   void AppendArg(const std::string& value);
-  void AppendArgPath(const FilePath& value);
+  void AppendArgPath(const base::FilePath& value);
   void AppendArgNative(const StringType& value);
 
   // Append the switches and arguments from another command line to this one.
diff --git a/base/event_recorder.h b/base/event_recorder.h
index 979e8060ee97af..bff87ed494b6f6 100644
--- a/base/event_recorder.h
+++ b/base/event_recorder.h
@@ -15,10 +15,10 @@
 #include <windows.h>
 #endif
 
-class FilePath;
-
 namespace base {
 
+class FilePath;
+
 // A class for recording and playing back keyboard and mouse input events.
 //
 // Note - if you record events, and the playback with the windows in
diff --git a/base/file_path.h b/base/file_path.h
index 81de702531de8a..e5c4b846f1c37f 100644
--- a/base/file_path.h
+++ b/base/file_path.h
@@ -125,6 +125,8 @@
 class Pickle;
 class PickleIterator;
 
+namespace base {
+
 // An abstraction to isolate users from the differences between native
 // pathnames on different platforms.
 class BASE_EXPORT FilePath {
@@ -398,8 +400,13 @@ class BASE_EXPORT FilePath {
   StringType path_;
 };
 
+}  // namespace base
+
+// TODO(brettw) remove this once callers properly use the base namespace.
+using base::FilePath;
+
 // This is required by googletest to print a readable output on test failures.
-BASE_EXPORT extern void PrintTo(const FilePath& path, std::ostream* out);
+BASE_EXPORT extern void PrintTo(const base::FilePath& path, std::ostream* out);
 
 // Macros for string literal initialization of FilePath::CharType[], and for
 // using a FilePath::CharType[] in a printf-style format string.
@@ -419,15 +426,15 @@ namespace BASE_HASH_NAMESPACE {
 #if defined(COMPILER_GCC)
 
 template<>
-struct hash<FilePath> {
-  size_t operator()(const FilePath& f) const {
-    return hash<FilePath::StringType>()(f.value());
+struct hash<base::FilePath> {
+  size_t operator()(const base::FilePath& f) const {
+    return hash<base::FilePath::StringType>()(f.value());
   }
 };
 
 #elif defined(COMPILER_MSVC)
 
-inline size_t hash_value(const FilePath& f) {
+inline size_t hash_value(const base::FilePath& f) {
   return hash_value(f.value());
 }
 
diff --git a/base/file_util.h b/base/file_util.h
index ffa4399fdd6503..b4500875db9928 100644
--- a/base/file_util.h
+++ b/base/file_util.h
@@ -49,19 +49,20 @@ extern bool g_bug108724_debug;
 // Functions that operate purely on a path string w/o touching the filesystem:
 
 // Returns true if the given path ends with a path separator character.
-BASE_EXPORT bool EndsWithSeparator(const FilePath& path);
+BASE_EXPORT bool EndsWithSeparator(const base::FilePath& path);
 
 // Makes sure that |path| ends with a separator IFF path is a directory that
 // exists. Returns true if |path| is an existing directory, false otherwise.
-BASE_EXPORT bool EnsureEndsWithSeparator(FilePath* path);
+BASE_EXPORT bool EnsureEndsWithSeparator(base::FilePath* path);
 
 // Convert provided relative path into an absolute path.  Returns false on
 // error. On POSIX, this function fails if the path does not exist.
-BASE_EXPORT bool AbsolutePath(FilePath* path);
+BASE_EXPORT bool AbsolutePath(base::FilePath* path);
 
 // Returns true if |parent| contains |child|. Both paths are converted to
 // absolute paths before doing the comparison.
-BASE_EXPORT bool ContainsPath(const FilePath& parent, const FilePath& child);
+BASE_EXPORT bool ContainsPath(const base::FilePath& parent,
+                              const base::FilePath& child);
 
 //-----------------------------------------------------------------------------
 // Functions that involve filesystem access or modification:
@@ -74,7 +75,7 @@ BASE_EXPORT bool ContainsPath(const FilePath& parent, const FilePath& child);
 // timestmap of file creation time. If you need to avoid such
 // mis-detection perfectly, you should wait one second before
 // obtaining |file_time|.
-BASE_EXPORT int CountFilesCreatedAfter(const FilePath& path,
+BASE_EXPORT int CountFilesCreatedAfter(const base::FilePath& path,
                                        const base::Time& file_time);
 
 // Returns the total number of bytes used by all the files under |root_path|.
@@ -82,7 +83,7 @@ BASE_EXPORT int CountFilesCreatedAfter(const FilePath& path,
 //
 // This function is implemented using the FileEnumerator class so it is not
 // particularly speedy in any platform.
-BASE_EXPORT int64 ComputeDirectorySize(const FilePath& root_path);
+BASE_EXPORT int64 ComputeDirectorySize(const base::FilePath& root_path);
 
 // Returns the total number of bytes used by all files matching the provided
 // |pattern|, on this |directory| (without recursion). If the path does not
@@ -90,8 +91,8 @@ BASE_EXPORT int64 ComputeDirectorySize(const FilePath& root_path);
 //
 // This function is implemented using the FileEnumerator class so it is not
 // particularly speedy in any platform.
-BASE_EXPORT int64 ComputeFilesSize(const FilePath& directory,
-                                   const FilePath::StringType& pattern);
+BASE_EXPORT int64 ComputeFilesSize(const base::FilePath& directory,
+                                   const base::FilePath::StringType& pattern);
 
 // Deletes the given path, whether it's a file or a directory.
 // If it's a directory, it's perfectly happy to delete all of the
@@ -104,7 +105,7 @@ BASE_EXPORT int64 ComputeFilesSize(const FilePath& directory,
 //
 // WARNING: USING THIS WITH recursive==true IS EQUIVALENT
 //          TO "rm -rf", SO USE WITH CAUTION.
-BASE_EXPORT bool Delete(const FilePath& path, bool recursive);
+BASE_EXPORT bool Delete(const base::FilePath& path, bool recursive);
 
 #if defined(OS_WIN)
 // Schedules to delete the given path, whether it's a file or a directory, until
@@ -112,25 +113,27 @@ BASE_EXPORT bool Delete(const FilePath& path, bool recursive);
 // Note:
 // 1) The file/directory to be deleted should exist in a temp folder.
 // 2) The directory to be deleted must be empty.
-BASE_EXPORT bool DeleteAfterReboot(const FilePath& path);
+BASE_EXPORT bool DeleteAfterReboot(const base::FilePath& path);
 #endif
 
 // Moves the given path, whether it's a file or a directory.
 // If a simple rename is not possible, such as in the case where the paths are
 // on different volumes, this will attempt to copy and delete. Returns
 // true for success.
-BASE_EXPORT bool Move(const FilePath& from_path, const FilePath& to_path);
+BASE_EXPORT bool Move(const base::FilePath& from_path,
+                      const base::FilePath& to_path);
 
 // Renames file |from_path| to |to_path|. Both paths must be on the same
 // volume, or the function will fail. Destination file will be created
 // if it doesn't exist. Prefer this function over Move when dealing with
 // temporary files. On Windows it preserves attributes of the target file.
 // Returns true on success.
-BASE_EXPORT bool ReplaceFile(const FilePath& from_path,
-                             const FilePath& to_path);
+BASE_EXPORT bool ReplaceFile(const base::FilePath& from_path,
+                             const base::FilePath& to_path);
 
 // Copies a single file. Use CopyDirectory to copy directories.
-BASE_EXPORT bool CopyFile(const FilePath& from_path, const FilePath& to_path);
+BASE_EXPORT bool CopyFile(const base::FilePath& from_path,
+                          const base::FilePath& to_path);
 
 // Copies the given path, and optionally all subdirectories and their contents
 // as well.
@@ -139,36 +142,37 @@ BASE_EXPORT bool CopyFile(const FilePath& from_path, const FilePath& to_path);
 // Don't use wildcards on the names, it may stop working without notice.
 //
 // If you only need to copy a file use CopyFile, it's faster.
-BASE_EXPORT bool CopyDirectory(const FilePath& from_path,
-                               const FilePath& to_path,
+BASE_EXPORT bool CopyDirectory(const base::FilePath& from_path,
+                               const base::FilePath& to_path,
                                bool recursive);
 
 // Returns true if the given path exists on the local filesystem,
 // false otherwise.
-BASE_EXPORT bool PathExists(const FilePath& path);
+BASE_EXPORT bool PathExists(const base::FilePath& path);
 
 // Returns true if the given path is writable by the user, false otherwise.
-BASE_EXPORT bool PathIsWritable(const FilePath& path);
+BASE_EXPORT bool PathIsWritable(const base::FilePath& path);
 
 // Returns true if the given path exists and is a directory, false otherwise.
-BASE_EXPORT bool DirectoryExists(const FilePath& path);
+BASE_EXPORT bool DirectoryExists(const base::FilePath& path);
 
 // Returns true if the contents of the two files given are equal, false
 // otherwise.  If either file can't be read, returns false.
-BASE_EXPORT bool ContentsEqual(const FilePath& filename1,
-                               const FilePath& filename2);
+BASE_EXPORT bool ContentsEqual(const base::FilePath& filename1,
+                               const base::FilePath& filename2);
 
 // Returns true if the contents of the two text files given are equal, false
 // otherwise.  This routine treats "\r\n" and "\n" as equivalent.
-BASE_EXPORT bool TextContentsEqual(const FilePath& filename1,
-                                   const FilePath& filename2);
+BASE_EXPORT bool TextContentsEqual(const base::FilePath& filename1,
+                                   const base::FilePath& filename2);
 
 // Read the file at |path| into |contents|, returning true on success.
 // This function fails if the |path| contains path traversal components ('..').
 // |contents| may be NULL, in which case this function is useful for its
 // side effect of priming the disk cache.
 // Useful for unit tests.
-BASE_EXPORT bool ReadFileToString(const FilePath& path, std::string* contents);
+BASE_EXPORT bool ReadFileToString(const base::FilePath& path,
+                                  std::string* contents);
 
 #if defined(OS_POSIX)
 // Read exactly |bytes| bytes from file descriptor |fd|, storing the result
@@ -178,12 +182,13 @@ BASE_EXPORT bool ReadFromFD(int fd, char* buffer, size_t bytes);
 
 // Creates a symbolic link at |symlink| pointing to |target|.  Returns
 // false on failure.
-BASE_EXPORT bool CreateSymbolicLink(const FilePath& target,
-                                    const FilePath& symlink);
+BASE_EXPORT bool CreateSymbolicLink(const base::FilePath& target,
+                                    const base::FilePath& symlink);
 
 // Reads the given |symlink| and returns where it points to in |target|.
 // Returns false upon failure.
-BASE_EXPORT bool ReadSymbolicLink(const FilePath& symlink, FilePath* target);
+BASE_EXPORT bool ReadSymbolicLink(const base::FilePath& symlink,
+                                  base::FilePath* target);
 
 // Bits ans masks of the file permission.
 enum FilePermissionBits {
@@ -206,11 +211,11 @@ enum FilePermissionBits {
 // Reads the permission of the given |path|, storing the file permission
 // bits in |mode|. If |path| is symbolic link, |mode| is the permission of
 // a file which the symlink points to.
-BASE_EXPORT bool GetPosixFilePermissions(const FilePath& path,
+BASE_EXPORT bool GetPosixFilePermissions(const base::FilePath& path,
                                          int* mode);
 // Sets the permission of the given |path|. If |path| is symbolic link, sets
 // the permission of a file which the symlink points to.
-BASE_EXPORT bool SetPosixFilePermissions(const FilePath& path,
+BASE_EXPORT bool SetPosixFilePermissions(const base::FilePath& path,
                                          int mode);
 #endif  // defined(OS_POSIX)
 
@@ -219,74 +224,76 @@ BASE_EXPORT bool SetPosixFilePermissions(const FilePath& path,
 // Returns true if all operations succeed.
 // This function simulates Move(), but unlike Move() it works across volumes.
 // This fuction is not transactional.
-BASE_EXPORT bool CopyAndDeleteDirectory(const FilePath& from_path,
-                                        const FilePath& to_path);
+BASE_EXPORT bool CopyAndDeleteDirectory(const base::FilePath& from_path,
+                                        const base::FilePath& to_path);
 #endif  // defined(OS_WIN)
 
 // Return true if the given directory is empty
-BASE_EXPORT bool IsDirectoryEmpty(const FilePath& dir_path);
+BASE_EXPORT bool IsDirectoryEmpty(const base::FilePath& dir_path);
 
 // Get the temporary directory provided by the system.
 // WARNING: DON'T USE THIS. If you want to create a temporary file, use one of
 // the functions below.
-BASE_EXPORT bool GetTempDir(FilePath* path);
+BASE_EXPORT bool GetTempDir(base::FilePath* path);
 // Get a temporary directory for shared memory files.
 // Only useful on POSIX; redirects to GetTempDir() on Windows.
-BASE_EXPORT bool GetShmemTempDir(FilePath* path, bool executable);
+BASE_EXPORT bool GetShmemTempDir(base::FilePath* path, bool executable);
 
 // Get the home directory.  This is more complicated than just getenv("HOME")
 // as it knows to fall back on getpwent() etc.
-BASE_EXPORT FilePath GetHomeDir();
+BASE_EXPORT base::FilePath GetHomeDir();
 
 // Creates a temporary file. The full path is placed in |path|, and the
 // function returns true if was successful in creating the file. The file will
 // be empty and all handles closed after this function returns.
-BASE_EXPORT bool CreateTemporaryFile(FilePath* path);
+BASE_EXPORT bool CreateTemporaryFile(base::FilePath* path);
 
 // Same as CreateTemporaryFile but the file is created in |dir|.
-BASE_EXPORT bool CreateTemporaryFileInDir(const FilePath& dir,
-                                          FilePath* temp_file);
+BASE_EXPORT bool CreateTemporaryFileInDir(const base::FilePath& dir,
+                                          base::FilePath* temp_file);
 
 // Create and open a temporary file.  File is opened for read/write.
 // The full path is placed in |path|.
 // Returns a handle to the opened file or NULL if an error occured.
-BASE_EXPORT FILE* CreateAndOpenTemporaryFile(FilePath* path);
+BASE_EXPORT FILE* CreateAndOpenTemporaryFile(base::FilePath* path);
 // Like above but for shmem files.  Only useful for POSIX.
 // The executable flag says the file needs to support using
 // mprotect with PROT_EXEC after mapping.
-BASE_EXPORT FILE* CreateAndOpenTemporaryShmemFile(FilePath* path,
+BASE_EXPORT FILE* CreateAndOpenTemporaryShmemFile(base::FilePath* path,
                                                   bool executable);
 // Similar to CreateAndOpenTemporaryFile, but the file is created in |dir|.
-BASE_EXPORT FILE* CreateAndOpenTemporaryFileInDir(const FilePath& dir,
-                                                  FilePath* path);
+BASE_EXPORT FILE* CreateAndOpenTemporaryFileInDir(const base::FilePath& dir,
+                                                  base::FilePath* path);
 
 // Create a new directory. If prefix is provided, the new directory name is in
 // the format of prefixyyyy.
 // NOTE: prefix is ignored in the POSIX implementation.
 // If success, return true and output the full path of the directory created.
-BASE_EXPORT bool CreateNewTempDirectory(const FilePath::StringType& prefix,
-                                        FilePath* new_temp_path);
+BASE_EXPORT bool CreateNewTempDirectory(
+    const base::FilePath::StringType& prefix,
+    base::FilePath* new_temp_path);
 
 // Create a directory within another directory.
 // Extra characters will be appended to |prefix| to ensure that the
 // new directory does not have the same name as an existing directory.
-BASE_EXPORT bool CreateTemporaryDirInDir(const FilePath& base_dir,
-                                         const FilePath::StringType& prefix,
-                                         FilePath* new_dir);
+BASE_EXPORT bool CreateTemporaryDirInDir(
+    const base::FilePath& base_dir,
+    const base::FilePath::StringType& prefix,
+    base::FilePath* new_dir);
 
 // Creates a directory, as well as creating any parent directories, if they
 // don't exist. Returns 'true' on successful creation, or if the directory
 // already exists.  The directory is only readable by the current user.
-BASE_EXPORT bool CreateDirectory(const FilePath& full_path);
+BASE_EXPORT bool CreateDirectory(const base::FilePath& full_path);
 
 // Returns the file size. Returns true on success.
-BASE_EXPORT bool GetFileSize(const FilePath& file_path, int64* file_size);
+BASE_EXPORT bool GetFileSize(const base::FilePath& file_path, int64* file_size);
 
 // Returns true if the given path's base name is ".".
-BASE_EXPORT bool IsDot(const FilePath& path);
+BASE_EXPORT bool IsDot(const base::FilePath& path);
 
 // Returns true if the given path's base name is "..".
-BASE_EXPORT bool IsDotDot(const FilePath& path);
+BASE_EXPORT bool IsDotDot(const base::FilePath& path);
 
 // Sets |real_path| to |path| with symbolic links and junctions expanded.
 // On windows, make sure the path starts with a lettered drive.
@@ -294,47 +301,48 @@ BASE_EXPORT bool IsDotDot(const FilePath& path);
 // a directory or to a nonexistent path.  On windows, this function will
 // fail if |path| is a junction or symlink that points to an empty file,
 // or if |real_path| would be longer than MAX_PATH characters.
-BASE_EXPORT bool NormalizeFilePath(const FilePath& path, FilePath* real_path);
+BASE_EXPORT bool NormalizeFilePath(const base::FilePath& path,
+                                   base::FilePath* real_path);
 
 #if defined(OS_WIN)
 
 // Given a path in NT native form ("\Device\HarddiskVolumeXX\..."),
 // return in |drive_letter_path| the equivalent path that starts with
 // a drive letter ("C:\...").  Return false if no such path exists.
-BASE_EXPORT bool DevicePathToDriveLetterPath(const FilePath& device_path,
-                                             FilePath* drive_letter_path);
+BASE_EXPORT bool DevicePathToDriveLetterPath(const base::FilePath& device_path,
+                                             base::FilePath* drive_letter_path);
 
 // Given an existing file in |path|, set |real_path| to the path
 // in native NT format, of the form "\Device\HarddiskVolumeXX\..".
 // Returns false if the path can not be found. Empty files cannot
 // be resolved with this function.
-BASE_EXPORT bool NormalizeToNativeFilePath(const FilePath& path,
-                                           FilePath* nt_path);
+BASE_EXPORT bool NormalizeToNativeFilePath(const base::FilePath& path,
+                                           base::FilePath* nt_path);
 #endif
 
 // This function will return if the given file is a symlink or not.
-BASE_EXPORT bool IsLink(const FilePath& file_path);
+BASE_EXPORT bool IsLink(const base::FilePath& file_path);
 
 // Returns information about the given file path.
-BASE_EXPORT bool GetFileInfo(const FilePath& file_path,
+BASE_EXPORT bool GetFileInfo(const base::FilePath& file_path,
                              base::PlatformFileInfo* info);
 
 // Sets the time of the last access and the time of the last modification.
-BASE_EXPORT bool TouchFile(const FilePath& path,
+BASE_EXPORT bool TouchFile(const base::FilePath& path,
                            const base::Time& last_accessed,
                            const base::Time& last_modified);
 
 // Set the time of the last modification. Useful for unit tests.
-BASE_EXPORT bool SetLastModifiedTime(const FilePath& path,
+BASE_EXPORT bool SetLastModifiedTime(const base::FilePath& path,
                                      const base::Time& last_modified);
 
 #if defined(OS_POSIX)
 // Store inode number of |path| in |inode|. Return true on success.
-BASE_EXPORT bool GetInode(const FilePath& path, ino_t* inode);
+BASE_EXPORT bool GetInode(const base::FilePath& path, ino_t* inode);
 #endif
 
 // Wrapper for fopen-like calls. Returns non-NULL FILE* on success.
-BASE_EXPORT FILE* OpenFile(const FilePath& filename, const char* mode);
+BASE_EXPORT FILE* OpenFile(const base::FilePath& filename, const char* mode);
 
 // Closes file opened by OpenFile. Returns true on success.
 BASE_EXPORT bool CloseFile(FILE* file);
@@ -345,32 +353,33 @@ BASE_EXPORT bool TruncateFile(FILE* file);
 
 // Reads the given number of bytes from the file into the buffer.  Returns
 // the number of read bytes, or -1 on error.
-BASE_EXPORT int ReadFile(const FilePath& filename, char* data, int size);
+BASE_EXPORT int ReadFile(const base::FilePath& filename, char* data, int size);
 
 // Writes the given buffer into the file, overwriting any data that was
 // previously there.  Returns the number of bytes written, or -1 on error.
-BASE_EXPORT int WriteFile(const FilePath& filename, const char* data, int size);
+BASE_EXPORT int WriteFile(const base::FilePath& filename, const char* data,
+                          int size);
 #if defined(OS_POSIX)
 // Append the data to |fd|. Does not close |fd| when done.
 BASE_EXPORT int WriteFileDescriptor(const int fd, const char* data, int size);
 #endif
 // Append the given buffer into the file. Returns the number of bytes written,
 // or -1 on error.
-BASE_EXPORT int AppendToFile(const FilePath& filename,
+BASE_EXPORT int AppendToFile(const base::FilePath& filename,
                              const char* data, int size);
 
 // Gets the current working directory for the process.
-BASE_EXPORT bool GetCurrentDirectory(FilePath* path);
+BASE_EXPORT bool GetCurrentDirectory(base::FilePath* path);
 
 // Sets the current working directory for the process.
-BASE_EXPORT bool SetCurrentDirectory(const FilePath& path);
+BASE_EXPORT bool SetCurrentDirectory(const base::FilePath& path);
 
 // Attempts to find a number that can be appended to the |path| to make it
 // unique. If |path| does not exist, 0 is returned.  If it fails to find such
 // a number, -1 is returned. If |suffix| is not empty, also checks the
 // existence of it with the given suffix.
-BASE_EXPORT int GetUniquePathNumber(const FilePath& path,
-                                    const FilePath::StringType& suffix);
+BASE_EXPORT int GetUniquePathNumber(const base::FilePath& path,
+                                    const base::FilePath::StringType& suffix);
 
 #if defined(OS_POSIX)
 // Test that |path| can only be changed by a given user and members of
@@ -384,8 +393,8 @@ BASE_EXPORT int GetUniquePathNumber(const FilePath& path,
 // * Are not symbolic links.
 // This is useful for checking that a config file is administrator-controlled.
 // |base| must contain |path|.
-BASE_EXPORT bool VerifyPathControlledByUser(const FilePath& base,
-                                            const FilePath& path,
+BASE_EXPORT bool VerifyPathControlledByUser(const base::FilePath& base,
+                                            const base::FilePath& path,
                                             uid_t owner_uid,
                                             const std::set<gid_t>& group_gids);
 #endif  // defined(OS_POSIX)
@@ -398,7 +407,7 @@ BASE_EXPORT bool VerifyPathControlledByUser(const FilePath& base,
 // the filesystem, are owned by the superuser, controlled by the group
 // "admin", are not writable by all users, and contain no symbolic links.
 // Will return false if |path| does not exist.
-BASE_EXPORT bool VerifyPathControlledByAdmin(const FilePath& path);
+BASE_EXPORT bool VerifyPathControlledByAdmin(const base::FilePath& path);
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 
 // A class to handle auto-closing of FILE*'s.
@@ -473,17 +482,17 @@ class BASE_EXPORT FileEnumerator {
   // NOTE: the pattern only matches the contents of root_path, not files in
   // recursive subdirectories.
   // TODO(erikkay): Fix the pattern matching to work at all levels.
-  FileEnumerator(const FilePath& root_path,
+  FileEnumerator(const base::FilePath& root_path,
                  bool recursive,
                  int file_type);
-  FileEnumerator(const FilePath& root_path,
+  FileEnumerator(const base::FilePath& root_path,
                  bool recursive,
                  int file_type,
-                 const FilePath::StringType& pattern);
+                 const base::FilePath::StringType& pattern);
   ~FileEnumerator();
 
   // Returns an empty string if there are no more results.
-  FilePath Next();
+  base::FilePath Next();
 
   // Write the file info into |info|.
   void GetFindInfo(FindInfo* info);
@@ -491,13 +500,13 @@ class BASE_EXPORT FileEnumerator {
   // Looks inside a FindInfo and determines if it's a directory.
   static bool IsDirectory(const FindInfo& info);
 
-  static FilePath GetFilename(const FindInfo& find_info);
+  static base::FilePath GetFilename(const FindInfo& find_info);
   static int64 GetFilesize(const FindInfo& find_info);
   static base::Time GetLastModifiedTime(const FindInfo& find_info);
 
  private:
   // Returns true if the given path should be skipped in enumeration.
-  bool ShouldSkip(const FilePath& path);
+  bool ShouldSkip(const base::FilePath& path);
 
 
 #if defined(OS_WIN)
@@ -507,13 +516,13 @@ class BASE_EXPORT FileEnumerator {
   HANDLE find_handle_;
 #elif defined(OS_POSIX)
   struct DirectoryEntryInfo {
-    FilePath filename;
+    base::FilePath filename;
     struct stat stat;
   };
 
   // Read the filenames in source into the vector of DirectoryEntryInfo's
   static bool ReadDirectory(std::vector<DirectoryEntryInfo>* entries,
-                            const FilePath& source, bool show_links);
+                            const base::FilePath& source, bool show_links);
 
   // The files in the current directory
   std::vector<DirectoryEntryInfo> directory_entries_;
@@ -522,14 +531,15 @@ class BASE_EXPORT FileEnumerator {
   size_t current_directory_entry_;
 #endif
 
-  FilePath root_path_;
+  base::FilePath root_path_;
   bool recursive_;
   int file_type_;
-  FilePath::StringType pattern_;  // Empty when we want to find everything.
+  base::FilePath::StringType pattern_;  // Empty when we want to find
+                                        // everything.
 
   // A stack that keeps track of which subdirectories we still need to
   // enumerate in the breadth-first search.
-  std::stack<FilePath> pending_paths_;
+  std::stack<base::FilePath> pending_paths_;
 
   DISALLOW_COPY_AND_ASSIGN(FileEnumerator);
 };
@@ -545,7 +555,7 @@ class BASE_EXPORT MemoryMappedFile {
   // then this method will fail and return false. If it cannot open the file,
   // the file does not exist, or the memory mapping fails, it will return false.
   // Later we may want to allow the user to specify access.
-  bool Initialize(const FilePath& file_name);
+  bool Initialize(const base::FilePath& file_name);
   // As above, but works with an already-opened file. MemoryMappedFile will take
   // ownership of |file| and close it when done.
   bool Initialize(base::PlatformFile file);
@@ -553,7 +563,7 @@ class BASE_EXPORT MemoryMappedFile {
 #if defined(OS_WIN)
   // Opens an existing file and maps it as an image section. Please refer to
   // the Initialize function above for additional information.
-  bool InitializeAsImageSection(const FilePath& file_name);
+  bool InitializeAsImageSection(const base::FilePath& file_name);
 #endif  // OS_WIN
 
   const uint8* data() const { return data_; }
@@ -564,7 +574,7 @@ class BASE_EXPORT MemoryMappedFile {
 
  private:
   // Open the given file and pass it to MapFileToMemoryInternal().
-  bool MapFileToMemory(const FilePath& file_name);
+  bool MapFileToMemory(const base::FilePath& file_name);
 
   // Map the file to memory, set data_ to that memory address. Return true on
   // success, false on any kind of failure. This is a helper for Initialize().
@@ -609,7 +619,8 @@ enum FileSystemType {
 
 // Attempts determine the FileSystemType for |path|.
 // Returns false if |path| doesn't exist.
-BASE_EXPORT bool GetFileSystemType(const FilePath& path, FileSystemType* type);
+BASE_EXPORT bool GetFileSystemType(const base::FilePath& path,
+                                   FileSystemType* type);
 #endif
 
 }  // namespace file_util
diff --git a/base/file_version_info.h b/base/file_version_info.h
index 84eec41b450678..bffa322e25a45c 100644
--- a/base/file_version_info.h
+++ b/base/file_version_info.h
@@ -18,7 +18,9 @@ extern "C" IMAGE_DOS_HEADER __ImageBase;
 #include "base/base_export.h"
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 // Provides an interface for accessing the version information for a file. This
 // is the information you access when you select a file in the Windows Explorer,
@@ -38,7 +40,7 @@ class FileVersionInfo {
   // goes wrong (typically the file does not exit or cannot be opened). The
   // returned object should be deleted when you are done with it.
   BASE_EXPORT static FileVersionInfo* CreateFileVersionInfo(
-      const FilePath& file_path);
+      const base::FilePath& file_path);
 #endif  // OS_WIN || OS_MACOSX
 
 #if defined(OS_WIN)
diff --git a/base/i18n/file_util_icu.h b/base/i18n/file_util_icu.h
index 4672135acb6e62..cf22e7c05e13c4 100644
--- a/base/i18n/file_util_icu.h
+++ b/base/i18n/file_util_icu.h
@@ -25,18 +25,18 @@ BASE_I18N_EXPORT bool IsFilenameLegal(const string16& file_name);
 //   file_name == "bad:file*name?.txt", changed to: "bad-file-name-.txt" when
 //   'replace_char' is '-'.
 BASE_I18N_EXPORT void ReplaceIllegalCharactersInPath(
-    FilePath::StringType* file_name,
+    base::FilePath::StringType* file_name,
     char replace_char);
 
 // Compares two filenames using the current locale information. This can be
 // used to sort directory listings. It behaves like "operator<" for use in
 // std::sort.
-BASE_I18N_EXPORT bool LocaleAwareCompareFilenames(const FilePath& a,
-                                                  const FilePath& b);
+BASE_I18N_EXPORT bool LocaleAwareCompareFilenames(const base::FilePath& a,
+                                                  const base::FilePath& b);
 
 // Calculates the canonical file-system representation of |file_name| base name.
 // Modifies |file_name| in place. No-op if not on ChromeOS.
-BASE_I18N_EXPORT void NormalizeFileNameEncoding(FilePath* file_name);
+BASE_I18N_EXPORT void NormalizeFileNameEncoding(base::FilePath* file_name);
 
 }  // namespace file_util
 
diff --git a/base/i18n/rtl.h b/base/i18n/rtl.h
index 202a126d71d311..2345931b675a0c 100644
--- a/base/i18n/rtl.h
+++ b/base/i18n/rtl.h
@@ -12,9 +12,10 @@
 #include "base/string16.h"
 #include "build/build_config.h"
 
+namespace base {
+
 class FilePath;
 
-namespace base {
 namespace i18n {
 
 const char16 kRightToLeftMark = 0x200F;
diff --git a/base/mac/bundle_locations.h b/base/mac/bundle_locations.h
index dd84b59e7b64f6..1d96539bf5c399 100644
--- a/base/mac/bundle_locations.h
+++ b/base/mac/bundle_locations.h
@@ -15,9 +15,10 @@ class NSBundle;
 class NSString;
 #endif  // __OBJC__
 
+namespace base {
+
 class FilePath;
 
-namespace base {
 namespace mac {
 
 // This file provides several functions to explicitly request the various
diff --git a/base/mac/foundation_util.h b/base/mac/foundation_util.h
index e6ad7840516993..0d78c554fb3107 100644
--- a/base/mac/foundation_util.h
+++ b/base/mac/foundation_util.h
@@ -28,8 +28,6 @@ class NSString;
 #include <ApplicationServices/ApplicationServices.h>
 #endif
 
-class FilePath;
-
 // Adapted from NSPathUtilities.h and NSObjCRuntime.h.
 #if __LP64__ || NS_BUILD_32_LIKE_64
 typedef unsigned long NSSearchPathDirectory;
@@ -43,6 +41,9 @@ typedef struct OpaqueSecTrustRef* SecACLRef;
 typedef struct OpaqueSecTrustedApplicationRef* SecTrustedApplicationRef;
 
 namespace base {
+
+class FilePath;
+
 namespace mac {
 
 // Returns true if the application is running from a bundle
diff --git a/base/mac/mac_util.h b/base/mac/mac_util.h
index 1a35b33ee07e8f..2190b24d13af11 100644
--- a/base/mac/mac_util.h
+++ b/base/mac/mac_util.h
@@ -21,9 +21,10 @@
 class NSImage;
 #endif  // __OBJC__
 
+namespace base {
+
 class FilePath;
 
-namespace base {
 namespace mac {
 
 // Full screen modes, in increasing order of priority.  More permissive modes
diff --git a/base/native_library.h b/base/native_library.h
index 845989dd4b8d27..37d72295d67850 100644
--- a/base/native_library.h
+++ b/base/native_library.h
@@ -26,10 +26,10 @@
 #define CDECL
 #endif
 
-class FilePath;
-
 namespace base {
 
+class FilePath;
+
 #if defined(OS_WIN)
 typedef HMODULE NativeLibrary;
 #elif defined(OS_MACOSX)
diff --git a/base/nix/mime_util_xdg.h b/base/nix/mime_util_xdg.h
index 444ce4f8e4ed28..79dba89d1dfef1 100644
--- a/base/nix/mime_util_xdg.h
+++ b/base/nix/mime_util_xdg.h
@@ -10,9 +10,10 @@
 #include "base/base_export.h"
 #include "build/build_config.h"
 
+namespace base {
+
 class FilePath;
 
-namespace base {
 namespace nix {
 
 // Gets the mime type for a file based on its filename. The file path does not
diff --git a/base/nix/xdg_util.h b/base/nix/xdg_util.h
index fc72663a2151c0..a8b778405f2f80 100644
--- a/base/nix/xdg_util.h
+++ b/base/nix/xdg_util.h
@@ -18,11 +18,10 @@
 #error asdf
 #endif
 
-class FilePath;
-
 namespace base {
 
 class Environment;
+class FilePath;
 
 namespace nix {
 
diff --git a/base/path_service.h b/base/path_service.h
index 8a7defe6e4ae7e..832b92b1581232 100644
--- a/base/path_service.h
+++ b/base/path_service.h
@@ -12,9 +12,8 @@
 #include "base/gtest_prod_util.h"
 #include "build/build_config.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class ScopedPathOverride;
 }  // namespace
 
@@ -30,7 +29,7 @@ class BASE_EXPORT PathService {
   //
   // Returns true if the directory or file was successfully retrieved. On
   // failure, 'path' will not be changed.
-  static bool Get(int key, FilePath* path);
+  static bool Get(int key, base::FilePath* path);
 
   // Overrides the path to a special directory or file.  This cannot be used to
   // change the value of DIR_CURRENT, but that should be obvious.  Also, if the
@@ -42,13 +41,13 @@ class BASE_EXPORT PathService {
   //
   // WARNING: Consumers of PathService::Get may expect paths to be constant
   // over the lifetime of the app, so this method should be used with caution.
-  static bool Override(int key, const FilePath& path);
+  static bool Override(int key, const base::FilePath& path);
 
   // This function does the same as PathService::Override but it takes an extra
   // parameter |create| which guides whether the directory to be overriden must
   // be created in case it doesn't exist already.
   static bool OverrideAndCreateIfNeeded(int key,
-                                        const FilePath& path,
+                                        const base::FilePath& path,
                                         bool create);
 
   // To extend the set of supported keys, you can register a path provider,
@@ -59,7 +58,7 @@ class BASE_EXPORT PathService {
   // WARNING: This function could be called on any thread from which the
   // PathService is used, so a the ProviderFunc MUST BE THREADSAFE.
   //
-  typedef bool (*ProviderFunc)(int, FilePath*);
+  typedef bool (*ProviderFunc)(int, base::FilePath*);
 
   // Call to register a path provider.  You must specify the range "[key_start,
   // key_end)" of supported path keys.
diff --git a/base/perftimer.h b/base/perftimer.h
index 1ac1a7d18901e2..9a23ff1d6fe5a3 100644
--- a/base/perftimer.h
+++ b/base/perftimer.h
@@ -10,14 +10,16 @@
 #include "base/basictypes.h"
 #include "base/time.h"
 
+namespace base {
 class FilePath;
+}
 
 // ----------------------------------------------------------------------
 // Initializes and finalizes the perf log. These functions should be
 // called at the beginning and end (respectively) of running all the
 // performance tests. The init function returns true on success.
 // ----------------------------------------------------------------------
-bool InitPerfLog(const FilePath& log_path);
+bool InitPerfLog(const base::FilePath& log_path);
 void FinalizePerfLog();
 
 // ----------------------------------------------------------------------
diff --git a/base/prefs/json_pref_store.h b/base/prefs/json_pref_store.h
index 49dd71ae1814b8..479d706dc133ff 100644
--- a/base/prefs/json_pref_store.h
+++ b/base/prefs/json_pref_store.h
@@ -20,12 +20,12 @@
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 class SequencedWorkerPool;
 class SequencedTaskRunner;
 class Value;
 }
 
-class FilePath;
 
 // A writable PrefStore implementation that is used for user preferences.
 class BASE_PREFS_EXPORT JsonPrefStore
@@ -35,12 +35,12 @@ class BASE_PREFS_EXPORT JsonPrefStore
   // Returns instance of SequencedTaskRunner which guarantees that file
   // operations on the same file will be executed in sequenced order.
   static scoped_refptr<base::SequencedTaskRunner> GetTaskRunnerForFile(
-      const FilePath& pref_filename,
+      const base::FilePath& pref_filename,
       base::SequencedWorkerPool* worker_pool);
 
   // |sequenced_task_runner| is must be a shutdown-blocking task runner, ideally
   // created by GetTaskRunnerForFile() method above.
-  JsonPrefStore(const FilePath& pref_filename,
+  JsonPrefStore(const base::FilePath& pref_filename,
                 base::SequencedTaskRunner* sequenced_task_runner);
 
   // PrefStore overrides:
@@ -78,7 +78,7 @@ class BASE_PREFS_EXPORT JsonPrefStore
   // ImportantFileWriter::DataSerializer overrides:
   virtual bool SerializeData(std::string* output) OVERRIDE;
 
-  FilePath path_;
+  base::FilePath path_;
   const scoped_refptr<base::SequencedTaskRunner> sequenced_task_runner_;
 
   scoped_ptr<base::DictionaryValue> prefs_;
diff --git a/base/prefs/public/pref_service_base.h b/base/prefs/public/pref_service_base.h
index 4115fa40703897..3508f402e194e5 100644
--- a/base/prefs/public/pref_service_base.h
+++ b/base/prefs/public/pref_service_base.h
@@ -18,6 +18,10 @@
 
 #include "base/values.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class BrowserContext;
 }
@@ -26,7 +30,6 @@ namespace subtle {
 class PrefMemberBase;
 }
 
-class FilePath;
 class PrefObserver;
 
 class PrefServiceBase {
@@ -118,7 +121,7 @@ class PrefServiceBase {
   virtual int GetInteger(const char* path) const = 0;
   virtual double GetDouble(const char* path) const = 0;
   virtual std::string GetString(const char* path) const = 0;
-  virtual FilePath GetFilePath(const char* path) const = 0;
+  virtual base::FilePath GetFilePath(const char* path) const = 0;
 
   // Returns the branch if it exists, or the registered default value otherwise.
   // Note that |path| must point to a registered preference. In that case, these
@@ -140,7 +143,7 @@ class PrefServiceBase {
   virtual void SetInteger(const char* path, int value) = 0;
   virtual void SetDouble(const char* path, double value) = 0;
   virtual void SetString(const char* path, const std::string& value) = 0;
-  virtual void SetFilePath(const char* path, const FilePath& value) = 0;
+  virtual void SetFilePath(const char* path, const base::FilePath& value) = 0;
 
   // Int64 helper methods that actually store the given value as a string.
   // Note that if obtaining the named value via GetDictionary or GetList, the
diff --git a/base/scoped_native_library.h b/base/scoped_native_library.h
index 94380bae1949a3..e9923f43424a63 100644
--- a/base/scoped_native_library.h
+++ b/base/scoped_native_library.h
@@ -8,10 +8,10 @@
 #include "base/base_export.h"
 #include "base/native_library.h"
 
-class FilePath;
-
 namespace base {
 
+class FilePath;
+
 // A class which encapsulates a base::NativeLibrary object available only in a
 // scope.
 // This class automatically unloads the loaded library in its destructor.
diff --git a/base/shared_memory.h b/base/shared_memory.h
index 30b1a892c8c616..da6f5b7b6ceed0 100644
--- a/base/shared_memory.h
+++ b/base/shared_memory.h
@@ -23,10 +23,10 @@
 #include "base/file_descriptor_posix.h"
 #endif
 
-class FilePath;
-
 namespace base {
 
+class FilePath;
+
 // SharedMemoryHandle is a platform specific type which represents
 // the underlying OS handle to a shared memory segment.
 #if defined(OS_WIN)
diff --git a/base/test/scoped_path_override.h b/base/test/scoped_path_override.h
index 3ac441cf60709b..bc88205b1e73b4 100644
--- a/base/test/scoped_path_override.h
+++ b/base/test/scoped_path_override.h
@@ -8,10 +8,10 @@
 #include "base/basictypes.h"
 #include "base/files/scoped_temp_dir.h"
 
-class FilePath;
-
 namespace base {
 
+class FilePath;
+
 // Sets a path override on construction, and removes it when the object goes out
 // of scope. This class is intended to be used by tests that need to override
 // paths to ensure their overrides are properly handled and reverted when the
diff --git a/base/test/test_file_util.h b/base/test/test_file_util.h
index 165af7092a1209..e97c0e55a0310c 100644
--- a/base/test/test_file_util.h
+++ b/base/test/test_file_util.h
@@ -12,18 +12,20 @@
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace file_util {
 
 // Wrapper over file_util::Delete. On Windows repeatedly invokes Delete in case
 // of failure to workaround Windows file locking semantics. Returns true on
 // success.
-bool DieFileDie(const FilePath& file, bool recurse);
+bool DieFileDie(const base::FilePath& file, bool recurse);
 
 // Clear a specific file from the system cache. After this call, trying
 // to access this file will result in a cold load from the hard drive.
-bool EvictFileFromSystemCache(const FilePath& file);
+bool EvictFileFromSystemCache(const base::FilePath& file);
 
 // Like CopyFileNoCache but recursively copies all files and subdirectories
 // in the given input directory to the output directory. Any files in the
@@ -31,39 +33,39 @@ bool EvictFileFromSystemCache(const FilePath& file);
 //
 // Returns true on success. False means there was some error copying, so the
 // state of the destination is unknown.
-bool CopyRecursiveDirNoCache(const FilePath& source_dir,
-                             const FilePath& dest_dir);
+bool CopyRecursiveDirNoCache(const base::FilePath& source_dir,
+                             const base::FilePath& dest_dir);
 
 #if defined(OS_WIN)
 // Returns true if the volume supports Alternate Data Streams.
-bool VolumeSupportsADS(const FilePath& path);
+bool VolumeSupportsADS(const base::FilePath& path);
 
 // Returns true if the ZoneIdentifier is correctly set to "Internet" (3).
 // Note that this function must be called from the same process as
 // the one that set the zone identifier.  I.e. don't use it in UI/automation
 // based tests.
-bool HasInternetZoneIdentifier(const FilePath& full_path);
+bool HasInternetZoneIdentifier(const base::FilePath& full_path);
 #endif  // defined(OS_WIN)
 
 // In general it's not reliable to convert a FilePath to a wstring and we use
 // string16 elsewhere for Unicode strings, but in tests it is frequently
 // convenient to be able to compare paths to literals like L"foobar".
-std::wstring FilePathAsWString(const FilePath& path);
-FilePath WStringAsFilePath(const std::wstring& path);
+std::wstring FilePathAsWString(const base::FilePath& path);
+base::FilePath WStringAsFilePath(const std::wstring& path);
 
 // For testing, make the file unreadable or unwritable.
 // In POSIX, this does not apply to the root user.
-bool MakeFileUnreadable(const FilePath& path) WARN_UNUSED_RESULT;
-bool MakeFileUnwritable(const FilePath& path) WARN_UNUSED_RESULT;
+bool MakeFileUnreadable(const base::FilePath& path) WARN_UNUSED_RESULT;
+bool MakeFileUnwritable(const base::FilePath& path) WARN_UNUSED_RESULT;
 
 // Saves the current permissions for a path, and restores it on destruction.
 class PermissionRestorer {
  public:
-  explicit PermissionRestorer(const FilePath& path);
+  explicit PermissionRestorer(const base::FilePath& path);
   ~PermissionRestorer();
 
  private:
-  const FilePath path_;
+  const base::FilePath path_;
   void* info_;  // The opaque stored permission information.
   size_t length_;  // The length of the stored permission information.
 
diff --git a/base/value_conversions.h b/base/value_conversions.h
index 99cd5143cb43cf..fde9a269299429 100644
--- a/base/value_conversions.h
+++ b/base/value_conversions.h
@@ -9,10 +9,10 @@
 
 #include "base/base_export.h"
 
-class FilePath;
 
 namespace base {
 
+class FilePath;
 class TimeDelta;
 class StringValue;
 class Value;
diff --git a/chrome/app/chrome_main_mac.h b/chrome/app/chrome_main_mac.h
index 232219dce09ecc..0de6cc8f2bf000 100644
--- a/chrome/app/chrome_main_mac.h
+++ b/chrome/app/chrome_main_mac.h
@@ -5,11 +5,13 @@
 #ifndef CHROME_APP_CHROME_MAIN_MAC_H_
 #define CHROME_APP_CHROME_MAIN_MAC_H_
 
+namespace base {
 class FilePath;
+}
 
 // Checks if the UserDataDir policy has been set and returns its value in the
 // |user_data_dir| parameter. If no policy is set the parameter is not changed.
-void CheckUserDataDirPolicy(FilePath* user_data_dir);
+void CheckUserDataDirPolicy(base::FilePath* user_data_dir);
 
 // Sets the app bundle (base::mac::FrameworkBundle()) to the framework's bundle,
 // and sets the base bundle ID (base::mac::BaseBundleID()) to the proper value
diff --git a/chrome/browser/automation/automation_provider.h b/chrome/browser/automation/automation_provider.h
index 657dc3a6dab815..a288308a3a3738 100644
--- a/chrome/browser/automation/automation_provider.h
+++ b/chrome/browser/automation/automation_provider.h
@@ -44,7 +44,6 @@ class AutomationTabTracker;
 class AutomationWindowTracker;
 class Browser;
 class ExternalTabContainer;
-class FilePath;
 class FindInPageNotificationObserver;
 class InitialLoadObserver;
 class LoginHandler;
diff --git a/chrome/browser/bookmarks/bookmark_pasteboard_helper_mac.h b/chrome/browser/bookmarks/bookmark_pasteboard_helper_mac.h
index ed15a166ba8cb4..c0dd000a1d08ce 100644
--- a/chrome/browser/bookmarks/bookmark_pasteboard_helper_mac.h
+++ b/chrome/browser/bookmarks/bookmark_pasteboard_helper_mac.h
@@ -11,7 +11,9 @@
 @class NSString;
 #endif  // __OBJC__
 
+namespace base {
 class FilePath;
+}
 
 // This set of functions lets C++ code interact with the cocoa pasteboard
 // and dragging methods.
@@ -25,12 +27,12 @@ enum PasteboardType {
 // Writes a set of bookmark elements from a profile to the specified pasteboard.
 void WriteToPasteboard(PasteboardType type,
                        const std::vector<BookmarkNodeData::Element>& elements,
-                       const FilePath& profile_path);
+                       const base::FilePath& profile_path);
 
 // Reads a set of bookmark elements from the specified pasteboard.
 bool ReadFromPasteboard(PasteboardType type,
                         std::vector<BookmarkNodeData::Element>& elements,
-                        FilePath* profile_path);
+                        base::FilePath* profile_path);
 
 // Returns true if the specified pasteboard contains any sort of
 // bookmark elements.  It currently does not consider a plaintext url a
diff --git a/chrome/browser/chromeos/customization_document.h b/chrome/browser/chromeos/customization_document.h
index 93cb59aa9ab933..e7a06e41737107 100644
--- a/chrome/browser/chromeos/customization_document.h
+++ b/chrome/browser/chromeos/customization_document.h
@@ -16,11 +16,11 @@
 #include "googleurl/src/gurl.h"
 #include "net/url_request/url_fetcher_delegate.h"
 
-class FilePath;
 class PrefServiceSimple;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace net {
@@ -44,7 +44,7 @@ class CustomizationDocument {
  protected:
   explicit CustomizationDocument(const std::string& accepted_version);
 
-  virtual bool LoadManifestFromFile(const FilePath& manifest_path);
+  virtual bool LoadManifestFromFile(const base::FilePath& manifest_path);
   virtual bool LoadManifestFromString(const std::string& manifest);
 
   std::string GetLocaleSpecificString(const std::string& locale,
@@ -158,7 +158,7 @@ class ServicesCustomizationDocument : public CustomizationDocument,
   void StartFileFetch();
 
   // Executes on FILE thread and reads file to string.
-  void ReadFileInBackground(const FilePath& file);
+  void ReadFileInBackground(const base::FilePath& file);
 
   // Services customization manifest URL.
   GURL url_;
diff --git a/chrome/browser/chromeos/drive/drive_feed_loader_observer.h b/chrome/browser/chromeos/drive/drive_feed_loader_observer.h
index 7232a783317e95..1d3e50450f3f55 100644
--- a/chrome/browser/chromeos/drive/drive_feed_loader_observer.h
+++ b/chrome/browser/chromeos/drive/drive_feed_loader_observer.h
@@ -7,7 +7,9 @@
 
 #include <string>
 
+namespace base {
 class FilePath;
+}
 
 namespace drive {
 
@@ -18,7 +20,7 @@ class DriveFeedLoaderObserver {
   // Triggered when a content of a directory has been changed.
   // |directory_path| is a virtual directory path representing the
   // changed directory.
-  virtual void OnDirectoryChanged(const FilePath& directory_path) {
+  virtual void OnDirectoryChanged(const base::FilePath& directory_path) {
   }
 
   // Triggered when a resource list is fetched. |num_accumulated_entries|
diff --git a/chrome/browser/chromeos/drive/drive_file_system_observer.h b/chrome/browser/chromeos/drive/drive_file_system_observer.h
index 4bc152077ff0e8..0d3a6789ee3438 100644
--- a/chrome/browser/chromeos/drive/drive_file_system_observer.h
+++ b/chrome/browser/chromeos/drive/drive_file_system_observer.h
@@ -7,7 +7,9 @@
 
 #include "chrome/browser/chromeos/drive/drive_file_error.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace drive {
 
@@ -19,7 +21,7 @@ class DriveFileSystemObserver {
   // Triggered when a content of a directory has been changed.
   // |directory_path| is a virtual directory path (/drive/...) representing
   // changed directory.
-  virtual void OnDirectoryChanged(const FilePath& directory_path) {
+  virtual void OnDirectoryChanged(const base::FilePath& directory_path) {
   }
 
   // Triggered when the file system is initially loaded.
diff --git a/chrome/browser/chromeos/drive/drive_file_system_util.h b/chrome/browser/chromeos/drive/drive_file_system_util.h
index c68be245ea3b9e..0f9a6a68148b54 100644
--- a/chrome/browser/chromeos/drive/drive_file_system_util.h
+++ b/chrome/browser/chromeos/drive/drive_file_system_util.h
@@ -16,9 +16,12 @@
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 #include "googleurl/src/gurl.h"
 
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace drive {
 
 class PlatformFileInfoProto;
@@ -39,13 +42,13 @@ const char kWildCard[] = "*";
 const char kSymLinkToDevNull[] = "/dev/null";
 
 // Returns the Drive mount point path, which looks like "/special/drive".
-const FilePath& GetDriveMountPointPath();
+const base::FilePath& GetDriveMountPointPath();
 
 // Returns the Drive mount path as string.
 const std::string& GetDriveMountPointPathAsString();
 
 // Returns the 'local' root of remote file system as "/special".
-const FilePath& GetSpecialRemoteRootPath();
+const base::FilePath& GetSpecialRemoteRootPath();
 
 // Returns the gdata file resource url formatted as
 // chrome://drive/<resource_id>/<file_name>.
@@ -54,16 +57,16 @@ GURL GetFileResourceUrl(const std::string& resource_id,
 
 // Given a profile and a drive_cache_path, return the file resource url.
 void ModifyDriveFileResourceUrl(Profile* profile,
-                                const FilePath& drive_cache_path,
+                                const base::FilePath& drive_cache_path,
                                 GURL* url);
 
 // Returns true if the given path is under the Drive mount point.
-bool IsUnderDriveMountPoint(const FilePath& path);
+bool IsUnderDriveMountPoint(const base::FilePath& path);
 
 // Extracts the Drive path from the given path located under the Drive mount
 // point. Returns an empty path if |path| is not under the Drive mount point.
 // Examples: ExtractGDatPath("/special/drive/foo.txt") => "drive/foo.txt"
-FilePath ExtractDrivePath(const FilePath& path);
+base::FilePath ExtractDrivePath(const base::FilePath& path);
 
 // Escapes a file name in Drive cache.
 // Replaces percent ('%'), period ('.') and slash ('/') with %XX (hex)
@@ -90,13 +93,13 @@ std::string ExtractResourceIdFromUrl(const GURL& url);
 // Case 3: Mounted files have all three parts.
 // Example: path="/user/GCache/v1/persistent/pdf:a1b2.01234567.mounted" =>
 //          resource_id="pdf:a1b2", md5="01234567", extra_extension="mounted".
-void ParseCacheFilePath(const FilePath& path,
+void ParseCacheFilePath(const base::FilePath& path,
                         std::string* resource_id,
                         std::string* md5,
                         std::string* extra_extension);
 
-// Callback type for PrepareWritableFilePathAndRun.
-typedef base::Callback<void (DriveFileError, const FilePath& path)>
+// Callback type for PrepareWritablebase::FilePathAndRun.
+typedef base::Callback<void (DriveFileError, const base::FilePath& path)>
     OpenFileCallback;
 
 // Invokes |callback| on blocking thread pool, after converting virtual |path|
@@ -108,7 +111,7 @@ typedef base::Callback<void (DriveFileError, const FilePath& path)>
 //
 // Must be called from UI thread.
 void PrepareWritableFileAndRun(Profile* profile,
-                               const FilePath& path,
+                               const base::FilePath& path,
                                const OpenFileCallback& callback);
 
 // Ensures the existence of |directory| of '/special/drive/foo'.  This will
@@ -122,7 +125,7 @@ void PrepareWritableFileAndRun(Profile* profile,
 //
 // Must be called from UI/IO thread.
 void EnsureDirectoryExists(Profile* profile,
-                           const FilePath& directory,
+                           const base::FilePath& directory,
                            const FileOperationCallback& callback);
 
 // Converts GData error code into file platform error code.
diff --git a/chrome/browser/chromeos/drive/drive_prefetcher.h b/chrome/browser/chromeos/drive/drive_prefetcher.h
index 39e08f9dbb223d..4bb599cd07ec00 100644
--- a/chrome/browser/chromeos/drive/drive_prefetcher.h
+++ b/chrome/browser/chromeos/drive/drive_prefetcher.h
@@ -17,7 +17,9 @@
 #include "chrome/browser/chromeos/drive/drive_file_system_observer.h"
 #include "chrome/browser/chromeos/drive/drive_sync_client_observer.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace drive {
 
@@ -45,7 +47,8 @@ class DrivePrefetcher : public DriveFileSystemObserver,
 
   // DriveFileSystemObserver overrides.
   virtual void OnInitialLoadFinished(DriveFileError error) OVERRIDE;
-  virtual void OnDirectoryChanged(const FilePath& directory_path) OVERRIDE;
+  virtual void OnDirectoryChanged(
+      const base::FilePath& directory_path) OVERRIDE;
 
   // DriveSyncClientObserver overrides.
   virtual void OnSyncTaskStarted() OVERRIDE;
@@ -63,7 +66,7 @@ class DrivePrefetcher : public DriveFileSystemObserver,
   // Called when DoPrefetch is done.
   void OnPrefetchFinished(const std::string& resource_id,
                           DriveFileError error,
-                          const FilePath& file_path,
+                          const base::FilePath& file_path,
                           const std::string& mime_type,
                           DriveFileType file_type);
 
@@ -72,8 +75,8 @@ class DrivePrefetcher : public DriveFileSystemObserver,
 
   // Helper methods to traverse over the file system.
   void VisitFile(const DriveEntryProto& entry);
-  void VisitDirectory(const FilePath& directory_path);
-  void OnReadDirectory(const FilePath& directory_path,
+  void VisitDirectory(const base::FilePath& directory_path);
+  void OnReadDirectory(const base::FilePath& directory_path,
                        DriveFileError error,
                        bool hide_hosted_documents,
                        scoped_ptr<DriveEntryProtoVector> entries);
diff --git a/chrome/browser/chromeos/drive/drive_system_service.h b/chrome/browser/chromeos/drive/drive_system_service.h
index d36cc289e93aa1..bbd0c8a20c2089 100644
--- a/chrome/browser/chromeos/drive/drive_system_service.h
+++ b/chrome/browser/chromeos/drive/drive_system_service.h
@@ -17,7 +17,9 @@
 #include "chrome/browser/profiles/profile_keyed_service_factory.h"
 #include "sync/notifier/invalidation_handler.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace google_apis {
 class DriveServiceInterface;
@@ -50,7 +52,7 @@ class DriveSystemService : public ProfileKeyedService,
   // Pass NULL or the empty value when not interested.
   DriveSystemService(Profile* profile,
                      google_apis::DriveServiceInterface* test_drive_service,
-                     const FilePath& test_cache_root,
+                     const base::FilePath& test_cache_root,
                      DriveFileSystemInterface* test_file_system);
   virtual ~DriveSystemService();
 
diff --git a/chrome/browser/chromeos/drive/drive_test_util.h b/chrome/browser/chromeos/drive/drive_test_util.h
index 7fc616b1892938..fedd04503872fe 100644
--- a/chrome/browser/chromeos/drive/drive_test_util.h
+++ b/chrome/browser/chromeos/drive/drive_test_util.h
@@ -10,9 +10,8 @@
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 #include "chrome/browser/google_apis/test_util.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class Value;
 }
 
@@ -51,9 +50,9 @@ void CopyErrorCodeFromFileOperationCallback(DriveFileError* output,
 // Copies |error| and |moved_file_path| to |out_error| and |out_file_path|.
 // Used to run asynchronous functions that take FileMoveCallback from tests.
 void CopyResultsFromFileMoveCallback(DriveFileError* out_error,
-                                     FilePath* out_file_path,
+                                     base::FilePath* out_file_path,
                                      DriveFileError error,
-                                     const FilePath& moved_file_path);
+                                     const base::FilePath& moved_file_path);
 
 // Copies |error| and |entry_proto| to |out_error| and |out_entry_proto|
 // respectively. Used to run asynchronous functions that take
@@ -85,14 +84,14 @@ void CopyResultsFromReadDirectoryByPathCallback(
 
 // Copies |error|, |drive_file_path|, and |entry_proto| to |out_error|,
 // |out_drive_file_path|, and |out_entry_proto| respectively. Used to run
-// asynchronous functions that take GetEntryInfoWithFilePathCallback from
+// asynchronous functions that take GetEntryInfoWithbase::FilePathCallback from
 // tests.
 void CopyResultsFromGetEntryInfoWithFilePathCallback(
     DriveFileError* out_error,
-    FilePath* out_drive_file_path,
+    base::FilePath* out_drive_file_path,
     scoped_ptr<DriveEntryProto>* out_entry_proto,
     DriveFileError error,
-    const FilePath& drive_file_path,
+    const base::FilePath& drive_file_path,
     scoped_ptr<DriveEntryProto> entry_proto);
 
 // Copies |result| to |out_result|. Used to run asynchronous functions
@@ -108,10 +107,11 @@ void CopyResultFromInitializeCacheCallback(bool* out_success,
 
 // Copies results from DriveCache methods. Used to run asynchronous functions
 // that take GetFileFromCacheCallback from tests.
-void CopyResultsFromGetFileFromCacheCallback(DriveFileError* out_error,
-                                             FilePath* out_cache_file_path,
-                                             DriveFileError error,
-                                             const FilePath& cache_file_path);
+void CopyResultsFromGetFileFromCacheCallback(
+    DriveFileError* out_error,
+    base::FilePath* out_cache_file_path,
+    DriveFileError error,
+    const base::FilePath& cache_file_path);
 
 // Copies results from DriveCache methods. Used to run asynchronous functions
 // that take GetCacheEntryCallback from tests.
@@ -123,10 +123,10 @@ void CopyResultsFromGetCacheEntryCallback(bool* out_success,
 // Copies results from DriveFileSystem methods. Used to run asynchronous
 // functions that take GetFileCallback from tests.
 void CopyResultsFromGetFileCallback(DriveFileError* out_error,
-                                    FilePath* out_file_path,
+                                    base::FilePath* out_file_path,
                                     DriveFileType* out_file_type,
                                     DriveFileError error,
-                                    const FilePath& file_path,
+                                    const base::FilePath& file_path,
                                     const std::string& mime_type,
                                     DriveFileType file_type);
 
@@ -143,9 +143,9 @@ void CopyResultsFromGetAvailableSpaceCallback(DriveFileError* out_error,
 // of the current thread. Used to run asynchronous function that take
 // OpenFileCallback.
 void CopyResultsFromOpenFileCallbackAndQuit(DriveFileError* out_error,
-                                            FilePath* out_file_path,
+                                            base::FilePath* out_file_path,
                                             DriveFileError error,
-                                            const FilePath& file_path);
+                                            const base::FilePath& file_path);
 
 // Copies the results from DriveFileSystem methods and stops the message loop
 // of the current thread. Used to run asynchronous function that take
diff --git a/chrome/browser/chromeos/drive/drive_webapps_registry.h b/chrome/browser/chromeos/drive/drive_webapps_registry.h
index 68270794efeab5..e907db55e23990 100644
--- a/chrome/browser/chromeos/drive/drive_webapps_registry.h
+++ b/chrome/browser/chromeos/drive/drive_webapps_registry.h
@@ -13,7 +13,9 @@
 #include "chrome/browser/google_apis/gdata_wapi_parser.h"
 #include "googleurl/src/gurl.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace google_apis {
 class AppList;
@@ -57,7 +59,7 @@ class DriveWebAppsRegistry {
   virtual ~DriveWebAppsRegistry();
 
   // DriveWebAppsRegistry overrides.
-  virtual void GetWebAppsForFile(const FilePath& file,
+  virtual void GetWebAppsForFile(const base::FilePath& file,
                                  const std::string& mime_type,
                                  ScopedVector<DriveWebAppInfo>* apps);
   virtual std::set<std::string> GetExtensionsForWebStoreApp(
diff --git a/chrome/browser/chromeos/drive/file_system/copy_operation.h b/chrome/browser/chromeos/drive/file_system/copy_operation.h
index 6ca1c5df3e295a..1f1ab25e7bdabe 100644
--- a/chrome/browser/chromeos/drive/file_system/copy_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/copy_operation.h
@@ -11,10 +11,10 @@
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class Value;
 }
 
@@ -49,8 +49,8 @@ class CopyOperation {
   // Performs the copy operation on the file at drive path |src_file_path|
   // with a target of |dest_file_path|. Invokes |callback| when finished with
   // the result of the operation. |callback| must not be null.
-  virtual void Copy(const FilePath& src_file_path,
-                    const FilePath& dest_file_path,
+  virtual void Copy(const base::FilePath& src_file_path,
+                    const base::FilePath& dest_file_path,
                     const FileOperationCallback& callback);
 
   // Initiates transfer of |remote_src_file_path| to |local_dest_file_path|.
@@ -60,8 +60,8 @@ class CopyOperation {
   // Must be called from *UI* thread. |callback| is run on the calling thread.
   // |callback| must not be null.
   virtual void TransferFileFromRemoteToLocal(
-      const FilePath& remote_src_file_path,
-      const FilePath& local_dest_file_path,
+      const base::FilePath& remote_src_file_path,
+      const base::FilePath& local_dest_file_path,
       const FileOperationCallback& callback);
 
   // Initiates transfer of |local_src_file_path| to |remote_dest_file_path|.
@@ -72,8 +72,8 @@ class CopyOperation {
   // Must be called from *UI* thread. |callback| is run on the calling thread.
   // |callback| must not be null.
   virtual void TransferFileFromLocalToRemote(
-      const FilePath& local_src_file_path,
-      const FilePath& remote_dest_file_path,
+      const base::FilePath& local_src_file_path,
+      const base::FilePath& remote_dest_file_path,
       const FileOperationCallback& callback);
 
   // Initiates transfer of |local_file_path| to |remote_dest_file_path|.
@@ -83,8 +83,8 @@ class CopyOperation {
   //
   // Must be called from *UI* thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  virtual void TransferRegularFile(const FilePath& local_file_path,
-                                   const FilePath& remote_dest_file_path,
+  virtual void TransferRegularFile(const base::FilePath& local_file_path,
+                                   const base::FilePath& remote_dest_file_path,
                                    const FileOperationCallback& callback);
 
  private:
@@ -98,27 +98,28 @@ class CopyOperation {
   //
   // Can be called from UI thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  void OnGetFileCompleteForTransferFile(const FilePath& local_dest_file_path,
-                                        const FileOperationCallback& callback,
-                                        DriveFileError error,
-                                        const FilePath& local_file_path,
-                                        const std::string& unused_mime_type,
-                                        DriveFileType file_type);
+  void OnGetFileCompleteForTransferFile(
+      const base::FilePath& local_dest_file_path,
+      const FileOperationCallback& callback,
+      DriveFileError error,
+      const base::FilePath& local_file_path,
+      const std::string& unused_mime_type,
+      DriveFileType file_type);
 
   // Copies a hosted document with |resource_id| to the directory at |dir_path|
   // and names the copied document as |new_name|.
   //
   // Can be called from UI thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  void CopyHostedDocumentToDirectory(const FilePath& dir_path,
+  void CopyHostedDocumentToDirectory(const base::FilePath& dir_path,
                                      const std::string& resource_id,
-                                     const FilePath::StringType& new_name,
+                                     const base::FilePath::StringType& new_name,
                                      const FileOperationCallback& callback);
 
   // Callback for handling document copy attempt.
   // |callback| must not be null.
   void OnCopyHostedDocumentCompleted(
-      const FilePath& dir_path,
+      const base::FilePath& dir_path,
       const FileOperationCallback& callback,
       google_apis::GDataErrorCode status,
       scoped_ptr<google_apis::ResourceEntry> resource_entry);
@@ -129,14 +130,14 @@ class CopyOperation {
   //
   // Can be called from UI thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  void MoveEntryFromRootDirectory(const FilePath& directory_path,
+  void MoveEntryFromRootDirectory(const base::FilePath& directory_path,
                                   const FileOperationCallback& callback,
                                   DriveFileError error,
-                                  const FilePath& file_path);
+                                  const base::FilePath& file_path);
 
   // Part of Copy(). Called after GetEntryInfoPairByPaths() is
   // complete. |callback| must not be null.
-  void CopyAfterGetEntryInfoPair(const FilePath& dest_file_path,
+  void CopyAfterGetEntryInfoPair(const base::FilePath& dest_file_path,
                                  const FileOperationCallback& callback,
                                  scoped_ptr<EntryInfoPairResult> result);
 
@@ -145,10 +146,10 @@ class CopyOperation {
   // |local_file_path| to |remote_dest_file_path|.
   //
   // Can be called from UI thread. |callback| is run on the calling thread.
-  void OnGetFileCompleteForCopy(const FilePath& remote_dest_file_path,
+  void OnGetFileCompleteForCopy(const base::FilePath& remote_dest_file_path,
                                 const FileOperationCallback& callback,
                                 DriveFileError error,
-                                const FilePath& local_file_path,
+                                const base::FilePath& local_file_path,
                                 const std::string& unused_mime_type,
                                 DriveFileType file_type);
 
@@ -170,15 +171,15 @@ class CopyOperation {
   void OnTransferCompleted(
       const FileOperationCallback& callback,
       google_apis::DriveUploadError error,
-      const FilePath& drive_path,
-      const FilePath& file_path,
+      const base::FilePath& drive_path,
+      const base::FilePath& file_path,
       scoped_ptr<google_apis::ResourceEntry> resource_entry);
 
   // Part of TransferFileFromLocalToRemote(). Called after
   // GetEntryInfoByPath() is complete.
   void TransferFileFromLocalToRemoteAfterGetEntryInfo(
-      const FilePath& local_src_file_path,
-      const FilePath& remote_dest_file_path,
+      const base::FilePath& local_src_file_path,
+      const base::FilePath& remote_dest_file_path,
       const FileOperationCallback& callback,
       DriveFileError error,
       scoped_ptr<DriveEntryProto> entry_proto);
@@ -192,8 +193,8 @@ class CopyOperation {
   //
   // Must be called from *UI* thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  void TransferFileForResourceId(const FilePath& local_file_path,
-                                 const FilePath& remote_dest_file_path,
+  void TransferFileForResourceId(const base::FilePath& local_file_path,
+                                 const base::FilePath& remote_dest_file_path,
                                  const FileOperationCallback& callback,
                                  const std::string& resource_id);
 
diff --git a/chrome/browser/chromeos/drive/file_system/drive_operations.h b/chrome/browser/chromeos/drive/file_system/drive_operations.h
index b9cd3e97b60445..1f188ace8b12a1 100644
--- a/chrome/browser/chromeos/drive/file_system/drive_operations.h
+++ b/chrome/browser/chromeos/drive/file_system/drive_operations.h
@@ -9,7 +9,9 @@
 #include "base/sequenced_task_runner.h"
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace google_apis {
 class DriveUploaderInterface;
@@ -52,37 +54,38 @@ class DriveOperations {
 
   // Wrapper function for copy_operation_.
   // |callback| must not be null.
-  void Copy(const FilePath& src_file_path,
-            const FilePath& dest_file_path,
+  void Copy(const base::FilePath& src_file_path,
+            const base::FilePath& dest_file_path,
             const FileOperationCallback& callback);
 
   // Wrapper function for copy_operation_.
   // |callback| must not be null.
-  void TransferFileFromRemoteToLocal(const FilePath& remote_src_file_path,
-                                     const FilePath& local_dest_file_path,
+  void TransferFileFromRemoteToLocal(const base::FilePath& remote_src_file_path,
+                                     const base::FilePath& local_dest_file_path,
                                      const FileOperationCallback& callback);
 
   // Wrapper function for copy_operation_.
   // |callback| must not be null.
-  void TransferFileFromLocalToRemote(const FilePath& local_src_file_path,
-                                     const FilePath& remote_dest_file_path,
-                                     const FileOperationCallback& callback);
+  void TransferFileFromLocalToRemote(
+      const base::FilePath& local_src_file_path,
+      const base::FilePath& remote_dest_file_path,
+      const FileOperationCallback& callback);
 
   // Wrapper function for copy_operation_.
   // |callback| must not be null.
-  void TransferRegularFile(const FilePath& local_src_file_path,
-                           const FilePath& remote_dest_file_path,
+  void TransferRegularFile(const base::FilePath& local_src_file_path,
+                           const base::FilePath& remote_dest_file_path,
                            const FileOperationCallback& callback);
 
   // Wrapper function for move_operation_.
   // |callback| must not be null.
-  void Move(const FilePath& src_file_path,
-            const FilePath& dest_file_path,
+  void Move(const base::FilePath& src_file_path,
+            const base::FilePath& dest_file_path,
             const FileOperationCallback& callback);
 
   // Wrapper function for remove_operation_.
   // |callback| must not be null.
-  void Remove(const FilePath& file_path,
+  void Remove(const base::FilePath& file_path,
               bool is_recursive,
               const FileOperationCallback& callback);
 
diff --git a/chrome/browser/chromeos/drive/file_system/move_operation.h b/chrome/browser/chromeos/drive/file_system/move_operation.h
index 2dd7ca926be298..2cf6cf9f7593cd 100644
--- a/chrome/browser/chromeos/drive/file_system/move_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/move_operation.h
@@ -11,9 +11,12 @@
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace drive {
 
 class DriveCache;
@@ -38,14 +41,14 @@ class MoveOperation {
   // Performs the move operation on the file at drive path |src_file_path|
   // with a target of |dest_file_path|.  Invokes |callback| when finished with
   // the result of the operation. |callback| must not be null.
-  virtual void Move(const FilePath& src_file_path,
-                    const FilePath& dest_file_path,
+  virtual void Move(const base::FilePath& src_file_path,
+                    const base::FilePath& dest_file_path,
                     const FileOperationCallback& callback);
  private:
   // Part of Move(). Called after GetEntryInfoPairByPaths() is
   // complete. |callback| must not be null.
   void MoveAfterGetEntryInfoPair(
-    const FilePath& dest_file_path,
+    const base::FilePath& dest_file_path,
     const FileOperationCallback& callback,
     scoped_ptr<EntryInfoPairResult> result);
 
@@ -53,7 +56,7 @@ class MoveOperation {
   // FileMoveCallback to FileOperationCallback.
   void OnFilePathUpdated(const FileOperationCallback& cllback,
                          DriveFileError error,
-                         const FilePath& file_path);
+                         const base::FilePath& file_path);
 
   // Renames a file or directory at |file_path| to |new_name| in the same
   // directory. |callback| will receive the new file path if the operation is
@@ -63,14 +66,14 @@ class MoveOperation {
   //
   // Can be called from UI thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  void Rename(const FilePath& file_path,
-              const FilePath::StringType& new_name,
+  void Rename(const base::FilePath& file_path,
+              const base::FilePath::StringType& new_name,
               const FileMoveCallback& callback);
 
   // Part of Rename(). Called after GetEntryInfoByPath() is complete.
   // |callback| must not be null.
-  void RenameAfterGetEntryInfo(const FilePath& file_path,
-                               const FilePath::StringType& new_name,
+  void RenameAfterGetEntryInfo(const base::FilePath& file_path,
+                               const base::FilePath::StringType& new_name,
                                const FileMoveCallback& callback,
                                DriveFileError error,
                                scoped_ptr<DriveEntryProto> entry_proto);
@@ -78,8 +81,8 @@ class MoveOperation {
   // Callback for handling resource rename attempt. Renames a file or
   // directory at |file_path| on the client side.
   // |callback| must not be null.
-  void RenameEntryLocally(const FilePath& file_path,
-                          const FilePath::StringType& new_name,
+  void RenameEntryLocally(const base::FilePath& file_path,
+                          const base::FilePath::StringType& new_name,
                           const FileMoveCallback& callback,
                           google_apis::GDataErrorCode status);
 
@@ -90,7 +93,7 @@ class MoveOperation {
   // |callback| must not be null.
   void RemoveEntryFromDirectory(const FileMoveCallback& callback,
                                 DriveFileError error,
-                                const FilePath& file_path);
+                                const base::FilePath& file_path);
 
   // Part of RemoveEntryFromDirectory(). Called after
   // GetEntryInfoPairByPaths() is complete. |callback| must not be null.
@@ -103,10 +106,10 @@ class MoveOperation {
   //
   // Can be called from UI thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  void AddEntryToDirectory(const FilePath& directory_path,
+  void AddEntryToDirectory(const base::FilePath& directory_path,
                            const FileOperationCallback& callback,
                            DriveFileError error,
-                           const FilePath& file_path);
+                           const base::FilePath& file_path);
 
   // Part of AddEntryToDirectory(). Called after
   // GetEntryInfoPairByPaths() is complete. |callback| must not be null.
@@ -117,8 +120,8 @@ class MoveOperation {
   // Moves entry specified by |file_path| to the directory specified by
   // |dir_path| and calls |callback| asynchronously.
   // |callback| must not be null.
-  void MoveEntryToDirectory(const FilePath& file_path,
-                            const FilePath& directory_path,
+  void MoveEntryToDirectory(const base::FilePath& file_path,
+                            const base::FilePath& directory_path,
                             const FileMoveCallback& callback,
                             google_apis::GDataErrorCode status);
 
@@ -128,7 +131,7 @@ class MoveOperation {
   void NotifyAndRunFileOperationCallback(
       const FileOperationCallback& callback,
       DriveFileError error,
-      const FilePath& moved_file_path);
+      const base::FilePath& moved_file_path);
 
   // Callback when an entry is moved to another directory on the client side.
   // Notifies the directory change and runs |callback|.
@@ -136,7 +139,7 @@ class MoveOperation {
   void NotifyAndRunFileMoveCallback(
       const FileMoveCallback& callback,
       DriveFileError error,
-      const FilePath& moved_file_path);
+      const base::FilePath& moved_file_path);
 
   DriveScheduler* drive_scheduler_;
   DriveResourceMetadata* metadata_;
diff --git a/chrome/browser/chromeos/drive/file_system/operation_observer.h b/chrome/browser/chromeos/drive/file_system/operation_observer.h
index 3c73f53e523ac4..bfa43332ed75da 100644
--- a/chrome/browser/chromeos/drive/file_system/operation_observer.h
+++ b/chrome/browser/chromeos/drive/file_system/operation_observer.h
@@ -5,7 +5,9 @@
 #ifndef CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_OPERATION_OBSERVER_H_
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_OPERATION_OBSERVER_H_
 
+namespace base {
 class FilePath;
+}
 
 namespace drive {
 namespace file_system {
@@ -17,7 +19,7 @@ class OperationObserver {
   // |directory_path| is a virtual directory path representing the
   // changed directory.
   virtual void OnDirectoryChangedByOperation(
-      const FilePath& directory_path) = 0;
+      const base::FilePath& directory_path) = 0;
 };
 
 }  // namespace file_system
diff --git a/chrome/browser/chromeos/drive/file_system/remove_operation.h b/chrome/browser/chromeos/drive/file_system/remove_operation.h
index f856eeb0c21485..df0c0d79a8ed59 100644
--- a/chrome/browser/chromeos/drive/file_system/remove_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/remove_operation.h
@@ -11,9 +11,12 @@
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace google_apis {
 }
 
@@ -42,7 +45,7 @@ class RemoveOperation {
   // Perform the remove operation on the file at drive path |file_path|.
   // Invokes |callback| when finished with the result of the operation.
   // |callback| must not be null.
-  virtual void Remove(const FilePath& file_path,
+  virtual void Remove(const base::FilePath& file_path,
                       bool is_recursive,
                       const FileOperationCallback& callback);
 
@@ -67,7 +70,7 @@ class RemoveOperation {
   void NotifyDirectoryChanged(
       const FileOperationCallback& callback,
       DriveFileError error,
-      const FilePath& directory_path);
+      const base::FilePath& directory_path);
 
   DriveScheduler* drive_scheduler_;
   DriveCache* cache_;
diff --git a/chrome/browser/chromeos/drive/file_system/update_operation.h b/chrome/browser/chromeos/drive/file_system/update_operation.h
index da0f39e94e321b..e4eb37b0c8026b 100644
--- a/chrome/browser/chromeos/drive/file_system/update_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/update_operation.h
@@ -11,9 +11,12 @@
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace google_apis {
 class DriveUploaderInterface;
 }
@@ -58,7 +61,7 @@ class UpdateOperation {
   void UpdateFileByEntryInfo(
       const FileOperationCallback& callback,
       DriveFileError error,
-      const FilePath& drive_file_path,
+      const base::FilePath& drive_file_path,
       scoped_ptr<DriveEntryProto> entry_proto);
 
   // Part of UpdateFileByResourceId().
@@ -66,10 +69,10 @@ class UpdateOperation {
   // UpdateFileByResourceId().
   // |callback| must not be null.
   void OnGetFileCompleteForUpdateFile(const FileOperationCallback& callback,
-                                      const FilePath& drive_file_path,
+                                      const base::FilePath& drive_file_path,
                                       scoped_ptr<DriveEntryProto> entry_proto,
                                       DriveFileError error,
-                                      const FilePath& cache_file_path);
+                                      const base::FilePath& cache_file_path);
 
   // Part of UpdateFileByResourceId().
   // Called when DriveUploader::UploadUpdatedFile() is completed for
@@ -78,15 +81,15 @@ class UpdateOperation {
   void OnUpdatedFileUploaded(
       const FileOperationCallback& callback,
       google_apis::DriveUploadError error,
-      const FilePath& gdata_path,
-      const FilePath& file_path,
+      const base::FilePath& gdata_path,
+      const base::FilePath& file_path,
       scoped_ptr<google_apis::ResourceEntry> resource_entry);
 
   // Part of UpdateFileByResourceId().
   // |callback| must not be null.
   void OnUpdatedFileRefreshed(const FileOperationCallback& callback,
                               DriveFileError error,
-                              const FilePath& drive_file_path,
+                              const base::FilePath& drive_file_path,
                               scoped_ptr<DriveEntryProto> entry_proto);
 
   DriveCache* cache_;
diff --git a/chrome/browser/chromeos/drive/file_write_helper.h b/chrome/browser/chromeos/drive/file_write_helper.h
index e1bf8f783d0f8c..da3021211d8f14 100644
--- a/chrome/browser/chromeos/drive/file_write_helper.h
+++ b/chrome/browser/chromeos/drive/file_write_helper.h
@@ -9,7 +9,9 @@
 #include "chrome/browser/chromeos/drive/drive_file_error.h"
 #include "chrome/browser/chromeos/drive/drive_file_system_interface.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace drive {
 
@@ -26,7 +28,7 @@ class FileWriteHelper {
   // file is created.
   //
   // Must be called from UI thread.
-  void PrepareWritableFileAndRun(const FilePath& path,
+  void PrepareWritableFileAndRun(const base::FilePath& path,
                                  const OpenFileCallback& callback);
 
  private:
@@ -34,15 +36,15 @@ class FileWriteHelper {
   // file does not exist yet, does OpenFile to download and mark the file as
   // dirty, runs |callback|, and finally calls CloseFile.
   void PrepareWritableFileAndRunAfterCreateFile(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       const OpenFileCallback& callback,
       DriveFileError result);
   void PrepareWritableFileAndRunAfterOpenFile(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       const OpenFileCallback& callback,
       DriveFileError result,
-      const FilePath& local_cache_path);
-  void PrepareWritableFileAndRunAfterCallback(const FilePath& file_path);
+      const base::FilePath& local_cache_path);
+  void PrepareWritableFileAndRunAfterCallback(const base::FilePath& file_path);
 
   // File system owned by DriveSystemService.
   DriveFileSystemInterface* file_system_;
diff --git a/chrome/browser/chromeos/enterprise_extension_observer.h b/chrome/browser/chromeos/enterprise_extension_observer.h
index 8ffd97cc8d9502..1f51da3c95bdae 100644
--- a/chrome/browser/chromeos/enterprise_extension_observer.h
+++ b/chrome/browser/chromeos/enterprise_extension_observer.h
@@ -13,9 +13,12 @@
 #include "content/public/browser/notification_source.h"
 #include "content/public/browser/notification_types.h"
 
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace chromeos {
 
 // This observer listens for installed extensions and restarts the ChromeOS
@@ -31,7 +34,7 @@ class EnterpriseExtensionObserver
                        const content::NotificationDetails& details) OVERRIDE;
 
  private:
-  static void CheckExtensionAndNotifyEntd(const FilePath& path);
+  static void CheckExtensionAndNotifyEntd(const base::FilePath& path);
   static void NotifyEntd();
 
   Profile* profile_;
diff --git a/chrome/browser/chromeos/imageburner/burn_controller.h b/chrome/browser/chromeos/imageburner/burn_controller.h
index e35ecd6860bccd..a0e62c904a4935 100644
--- a/chrome/browser/chromeos/imageburner/burn_controller.h
+++ b/chrome/browser/chromeos/imageburner/burn_controller.h
@@ -10,9 +10,8 @@
 #include "base/basictypes.h"
 #include "chromeos/disks/disk_mount_manager.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class TimeDelta;
 }
 
@@ -69,8 +68,8 @@ class BurnController {
   // Returns devices on which we can burn recovery image.
   virtual std::vector<disks::DiskMountManager::Disk> GetBurnableDevices() = 0;
   // Starts burning process.
-  virtual void StartBurnImage(const FilePath& target_device_path,
-                              const FilePath& target_file_path) = 0;
+  virtual void StartBurnImage(const base::FilePath& target_device_path,
+                              const base::FilePath& target_file_path) = 0;
   // Cancels burning process.
   virtual void CancelBurnImage() = 0;
   // Creates a new instance of BurnController.
diff --git a/chrome/browser/chromeos/login/user_image_manager.h b/chrome/browser/chromeos/login/user_image_manager.h
index f6e4ea4a7f6237..00bb9a77ed427c 100644
--- a/chrome/browser/chromeos/login/user_image_manager.h
+++ b/chrome/browser/chromeos/login/user_image_manager.h
@@ -9,9 +9,12 @@
 
 #include "chrome/browser/chromeos/login/user.h"
 
-class FilePath;
 class PrefServiceSimple;
 
+namespace base {
+class FilePath;
+}
+
 namespace gfx {
 class ImageSkia;
 }
@@ -49,7 +52,7 @@ class UserImageManager {
   // Tries to load user image from disk; if successful, sets it for the user,
   // sends LOGIN_USER_IMAGE_CHANGED notification and updates Local State.
   virtual void SaveUserImageFromFile(const std::string& username,
-                                     const FilePath& path) = 0;
+                                     const base::FilePath& path) = 0;
 
   // Sets profile image as user image for |username|, sends
   // LOGIN_USER_IMAGE_CHANGED notification and updates Local State. If the user
diff --git a/chrome/browser/chromeos/login/user_image_manager_impl.h b/chrome/browser/chromeos/login/user_image_manager_impl.h
index 448be5898a0cce..e6fb5340b2e88d 100644
--- a/chrome/browser/chromeos/login/user_image_manager_impl.h
+++ b/chrome/browser/chromeos/login/user_image_manager_impl.h
@@ -21,6 +21,10 @@
 class ProfileDownloader;
 class UserImage;
 
+namespace base {
+class FilePath;
+}
+
 namespace chromeos {
 
 class UserImageManagerImpl : public UserImageManager,
@@ -39,7 +43,7 @@ class UserImageManagerImpl : public UserImageManager,
   virtual void SaveUserImage(const std::string& username,
                              const UserImage& user_image) OVERRIDE;
   virtual void SaveUserImageFromFile(const std::string& username,
-                                     const FilePath& path) OVERRIDE;
+                                     const base::FilePath& path) OVERRIDE;
   virtual void SaveUserImageFromProfileImage(
       const std::string& username) OVERRIDE;
   virtual void DeleteUserImage(const std::string& username) OVERRIDE;
@@ -63,7 +67,7 @@ class UserImageManagerImpl : public UserImageManager,
       ProfileDownloaderDelegate::FailureReason reason) OVERRIDE;
 
   // Returns image filepath for the given user.
-  FilePath GetImagePathForUser(const std::string& username);
+  base::FilePath GetImagePathForUser(const std::string& username);
 
   // Sets one of the default images for the specified user and saves this
   // setting in local state.
@@ -90,7 +94,7 @@ class UserImageManagerImpl : public UserImageManager,
   // Local State on UI thread.
   void SaveImageToFile(const std::string& username,
                        const UserImage& user_image,
-                       const FilePath& image_path,
+                       const base::FilePath& image_path,
                        int image_index,
                        const GURL& image_url);
 
@@ -105,7 +109,7 @@ class UserImageManagerImpl : public UserImageManager,
 
   // Saves |image| to the specified |image_path|. Runs on FILE thread.
   bool SaveBitmapToFile(const UserImage& user_image,
-                        const FilePath& image_path);
+                        const base::FilePath& image_path);
 
   // Initializes |downloaded_profile_image_| with the picture of the logged-in
   // user.
diff --git a/chrome/browser/chromeos/login/user_manager_impl.h b/chrome/browser/chromeos/login/user_manager_impl.h
index c9bdf7c284ec8a..7d3c0f6a8552bd 100644
--- a/chrome/browser/chromeos/login/user_manager_impl.h
+++ b/chrome/browser/chromeos/login/user_manager_impl.h
@@ -24,7 +24,6 @@
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
-class FilePath;
 class PrefService;
 class ProfileSyncService;
 
diff --git a/chrome/browser/chromeos/mobile_config.h b/chrome/browser/chromeos/mobile_config.h
index d422ed4cd76606..1c98ff5f13cc0b 100644
--- a/chrome/browser/chromeos/mobile_config.h
+++ b/chrome/browser/chromeos/mobile_config.h
@@ -15,10 +15,9 @@
 #include "base/time.h"
 #include "chrome/browser/chromeos/customization_document.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace chromeos {
@@ -180,8 +179,8 @@ class MobileConfig : public CustomizationDocument  {
                      const std::string& local_config);
 
   // Executes on FILE thread and reads config files to string.
-  void ReadConfigInBackground(const FilePath& global_config_file,
-                              const FilePath& local_config_file);
+  void ReadConfigInBackground(const base::FilePath& global_config_file,
+                              const base::FilePath& local_config_file);
 
   // Maps external carrier ID to internal carrier ID.
   CarrierIdMap carrier_id_map_;
diff --git a/chrome/browser/chromeos/settings/owner_key_util.h b/chrome/browser/chromeos/settings/owner_key_util.h
index fc94394f73fcca..2568cfad2787ab 100644
--- a/chrome/browser/chromeos/settings/owner_key_util.h
+++ b/chrome/browser/chromeos/settings/owner_key_util.h
@@ -14,7 +14,9 @@
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace crypto {
 class RSAPrivateKey;
@@ -59,7 +61,7 @@ class OwnerKeyUtilImpl : public OwnerKeyUtil {
   // key will live.
   static const char kOwnerKeyFile[];
 
-  explicit OwnerKeyUtilImpl(const FilePath& public_key_file);
+  explicit OwnerKeyUtilImpl(const base::FilePath& public_key_file);
 
   // OwnerKeyUtil:
   virtual bool ImportPublicKey(std::vector<uint8>* output) OVERRIDE;
@@ -72,7 +74,7 @@ class OwnerKeyUtilImpl : public OwnerKeyUtil {
 
  private:
   // The file that holds the public key.
-  FilePath key_file_;
+  base::FilePath key_file_;
 
   DISALLOW_COPY_AND_ASSIGN(OwnerKeyUtilImpl);
 };
diff --git a/chrome/browser/chromeos/system/name_value_pairs_parser.h b/chrome/browser/chromeos/system/name_value_pairs_parser.h
index b35cd4c1eea731..a41a5ad555bc7f 100644
--- a/chrome/browser/chromeos/system/name_value_pairs_parser.h
+++ b/chrome/browser/chromeos/system/name_value_pairs_parser.h
@@ -10,7 +10,9 @@
 
 #include "base/basictypes.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chromeos {
 namespace system {
@@ -36,7 +38,7 @@ class NameValuePairsParser {
   // Parses name-value pairs from the file.
   // Returns false if there was any error in the file. Valid pairs will still be
   // added to the map.
-  bool GetNameValuePairsFromFile(const FilePath& file_path,
+  bool GetNameValuePairsFromFile(const base::FilePath& file_path,
                                  const std::string& eq,
                                  const std::string& delim);
 
diff --git a/chrome/browser/component_updater/component_updater_service.h b/chrome/browser/component_updater/component_updater_service.h
index 43a083f933acdf..ce17de0fb95b41 100644
--- a/chrome/browser/component_updater/component_updater_service.h
+++ b/chrome/browser/component_updater/component_updater_service.h
@@ -11,14 +11,13 @@
 #include "base/version.h"
 #include "googleurl/src/gurl.h"
 
-class FilePath;
-
 namespace net {
 class URLRequestContextGetter;
 }
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 // Component specific installers must derive from this class and implement
@@ -36,7 +35,7 @@ class ComponentInstaller {
   // json dictionary and |unpack_path| contains the temporary directory
   // with all the unpacked CRX files.
   virtual bool Install(base::DictionaryValue* manifest,
-                       const FilePath& unpack_path) = 0;
+                       const base::FilePath& unpack_path) = 0;
 
  protected:
   virtual ~ComponentInstaller() {}
diff --git a/chrome/browser/devtools/devtools_file_helper.h b/chrome/browser/devtools/devtools_file_helper.h
index 42fcb7d46a6c4e..e97e5bd7e0a04a 100644
--- a/chrome/browser/devtools/devtools_file_helper.h
+++ b/chrome/browser/devtools/devtools_file_helper.h
@@ -14,9 +14,12 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class WebContents;
 }
@@ -84,19 +87,21 @@ class DevToolsFileHelper {
   void SaveAsFileSelected(const std::string& url,
                           const std::string& content,
                           const SaveCallback& callback,
-                          const FilePath& path);
+                          const base::FilePath& path);
   void SaveAsFileSelectionCanceled();
   void InnerAddFileSystem(const AddFileSystemCallback& callback,
-                          const FilePath& path);
-  void AddValidatedFileSystem(const AddFileSystemCallback& callback,
-                              const std::vector<FilePath>& permitted_paths);
-  void RestoreValidatedFileSystems(const RequestFileSystemsCallback& callback,
-                                   const std::vector<FilePath>& file_paths);
+                          const base::FilePath& path);
+  void AddValidatedFileSystem(
+      const AddFileSystemCallback& callback,
+      const std::vector<base::FilePath>& permitted_paths);
+  void RestoreValidatedFileSystems(
+      const RequestFileSystemsCallback& callback,
+      const std::vector<base::FilePath>& file_paths);
 
   content::WebContents* web_contents_;
   Profile* profile_;
   base::WeakPtrFactory<DevToolsFileHelper> weak_factory_;
-  typedef std::map<std::string, FilePath> PathsMap;
+  typedef std::map<std::string, base::FilePath> PathsMap;
   PathsMap saved_files_;
   DISALLOW_COPY_AND_ASSIGN(DevToolsFileHelper);
 };
diff --git a/chrome/browser/diagnostics/diagnostics_test.h b/chrome/browser/diagnostics/diagnostics_test.h
index 571145ba5eb075..d1c430a2a1676c 100644
--- a/chrome/browser/diagnostics/diagnostics_test.h
+++ b/chrome/browser/diagnostics/diagnostics_test.h
@@ -9,7 +9,9 @@
 #include "base/string16.h"
 #include "chrome/browser/diagnostics/diagnostics_model.h"
 
+namespace base {
 class FilePath;
+}
 
 // Represents a single diagnostic test and encapsulates the common
 // functionality across platforms as well.
@@ -55,7 +57,7 @@ class DiagnosticTest : public DiagnosticsModel::TestInfo {
   void RecordOutcome(const string16& additional_info,
                      DiagnosticsModel::TestResult result);
 
-  static FilePath GetUserDefaultProfileDir();
+  static base::FilePath GetUserDefaultProfileDir();
 
  protected:
   // The id needs to be overridden by derived classes and must uniquely
diff --git a/chrome/browser/download/download_file_picker.h b/chrome/browser/download/download_file_picker.h
index 28f661b3131001..b7dc8b42f4c78c 100644
--- a/chrome/browser/download/download_file_picker.h
+++ b/chrome/browser/download/download_file_picker.h
@@ -8,7 +8,9 @@
 #include "chrome/browser/download/chrome_download_manager_delegate.h"
 #include "ui/shell_dialogs/select_file_dialog.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 class DownloadItem;
@@ -24,7 +26,7 @@ class DownloadFilePicker : public ui::SelectFileDialog::Listener {
 
   void Init(content::DownloadManager* download_manager,
             content::DownloadItem* item,
-            const FilePath& suggested_path,
+            const base::FilePath& suggested_path,
             const ChromeDownloadManagerDelegate::FileSelectedCallback&
                 callback);
 
@@ -33,28 +35,28 @@ class DownloadFilePicker : public ui::SelectFileDialog::Listener {
   // method should be overridden to set the correct suggested path to prompt the
   // user.
   virtual void InitSuggestedPath(content::DownloadItem* item,
-                                 const FilePath& suggested_path);
+                                 const base::FilePath& suggested_path);
 
-  void set_suggested_path(const FilePath& suggested_path) {
+  void set_suggested_path(const base::FilePath& suggested_path) {
     suggested_path_ = suggested_path;
   }
 
   // Runs |file_selected_callback_| with |path| and then deletes this object.
-  void OnFileSelected(const FilePath& path);
+  void OnFileSelected(const base::FilePath& path);
 
-  void RecordFileSelected(const FilePath& path);
+  void RecordFileSelected(const base::FilePath& path);
 
   scoped_refptr<content::DownloadManager> download_manager_;
   int32 download_id_;
 
  private:
   // SelectFileDialog::Listener implementation.
-  virtual void FileSelected(const FilePath& path,
+  virtual void FileSelected(const base::FilePath& path,
                             int index,
                             void* params) OVERRIDE;
   virtual void FileSelectionCanceled(void* params) OVERRIDE;
 
-  FilePath suggested_path_;
+  base::FilePath suggested_path_;
 
   ChromeDownloadManagerDelegate::FileSelectedCallback file_selected_callback_;
 
diff --git a/chrome/browser/download/download_path_reservation_tracker.h b/chrome/browser/download/download_path_reservation_tracker.h
index 9bfeea78e49845..7c7775b063f5f9 100644
--- a/chrome/browser/download/download_path_reservation_tracker.h
+++ b/chrome/browser/download/download_path_reservation_tracker.h
@@ -63,12 +63,14 @@
 // It considers 'foo/bar/x.pdf' and 'foo/baz/x.pdf' to be two different paths,
 // even though 'bar' might be a symlink to 'baz'.
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class DownloadItem;
 }
 
-class FilePath;
-
 // Issues and tracks download paths that are in use by the download system. When
 // a target path is set for a download, this object tracks the path and the
 // associated download item so that subsequent downloads can avoid using the
@@ -84,7 +86,7 @@ class DownloadPathReservationTracker {
   //
   // If |requested_target_path| was not writeable, then the parent directory of
   // |target_path| may be different from that of |requested_target_path|.
-  typedef base::Callback<void(const FilePath& target_path,
+  typedef base::Callback<void(const base::FilePath& target_path,
                               bool target_path_verified)> ReservedPathCallback;
 
   // The largest index for the uniquification suffix that we will try while
@@ -99,14 +101,14 @@ class DownloadPathReservationTracker {
   // directory does not exist and is the parent directory of
   // |requested_target_path|, the directory will be created.
   static void GetReservedPath(content::DownloadItem& download_item,
-                              const FilePath& requested_target_path,
-                              const FilePath& default_download_path,
+                              const base::FilePath& requested_target_path,
+                              const base::FilePath& default_download_path,
                               bool should_uniquify_path,
                               const ReservedPathCallback& callback);
 
   // Returns true if |path| is in use by an existing path reservation. Should
   // only be called on the FILE thread. Currently only used by tests.
-  static bool IsPathInUseForTesting(const FilePath& path);
+  static bool IsPathInUseForTesting(const base::FilePath& path);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_PATH_RESERVATION_TRACKER_H_
diff --git a/chrome/browser/enumerate_modules_model_win.h b/chrome/browser/enumerate_modules_model_win.h
index aac4a9c25055e3..0d78ab07d57c11 100644
--- a/chrome/browser/enumerate_modules_model_win.h
+++ b/chrome/browser/enumerate_modules_model_win.h
@@ -17,9 +17,9 @@
 #include "googleurl/src/gurl.h"
 
 class EnumerateModulesModel;
-class FilePath;
 
 namespace base {
+class FilePath;
 class ListValue;
 }
 
@@ -191,7 +191,7 @@ class ModuleEnumerator : public base::RefCountedThreadSafe<ModuleEnumerator> {
 
   // Given a filename, returns the Subject (who signed it) retrieved from
   // the digital signature (Authenticode).
-  string16 GetSubjectNameFromDigitalSignature(const FilePath& filename);
+  string16 GetSubjectNameFromDigitalSignature(const base::FilePath& filename);
 
   // The typedef for the vector that maps a regular file path to %env_var%.
   typedef std::vector< std::pair<string16, string16> > PathMapping;
diff --git a/chrome/browser/extensions/activity_database.h b/chrome/browser/extensions/activity_database.h
index 89daecf661cb95..1c73dc9709cb98 100644
--- a/chrome/browser/extensions/activity_database.h
+++ b/chrome/browser/extensions/activity_database.h
@@ -14,7 +14,9 @@
 #include "sql/connection.h"
 #include "sql/init_status.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace extensions {
 
@@ -30,7 +32,7 @@ class ActivityDatabase : public base::RefCountedThreadSafe<ActivityDatabase> {
   void SetErrorDelegate(sql::ErrorDelegate* error_delegate);
 
   // Opens the DB and creates tables as necessary.
-  void Init(const FilePath& db_name);
+  void Init(const base::FilePath& db_name);
   void LogInitFailure();
 
   // Record a UrlAction in the database.
diff --git a/chrome/browser/extensions/api/bookmarks/bookmarks_api.h b/chrome/browser/extensions/api/bookmarks/bookmarks_api.h
index 1b12fd596d3c7f..44e2259eb0b819 100644
--- a/chrome/browser/extensions/api/bookmarks/bookmarks_api.h
+++ b/chrome/browser/extensions/api/bookmarks/bookmarks_api.h
@@ -17,9 +17,8 @@
 #include "chrome/browser/extensions/extension_function.h"
 #include "ui/shell_dialogs/select_file_dialog.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class ListValue;
 }
 
@@ -274,10 +273,10 @@ class BookmarksIOFunction : public BookmarksFunction,
  public:
   BookmarksIOFunction();
 
-  virtual void FileSelected(const FilePath& path, int index, void* params) = 0;
+  virtual void FileSelected(const base::FilePath& path, int index, void* params) = 0;
 
   // ui::SelectFileDialog::Listener:
-  virtual void MultiFilesSelected(const std::vector<FilePath>& files,
+  virtual void MultiFilesSelected(const std::vector<base::FilePath>& files,
                                   void* params) OVERRIDE;
   virtual void FileSelectionCanceled(void* params) OVERRIDE;
 
@@ -289,7 +288,7 @@ class BookmarksIOFunction : public BookmarksFunction,
  private:
   void ShowSelectFileDialog(
       ui::SelectFileDialog::Type type,
-      const FilePath& default_path);
+      const base::FilePath& default_path);
 
  protected:
   scoped_refptr<ui::SelectFileDialog> select_file_dialog_;
@@ -300,7 +299,7 @@ class BookmarksImportFunction : public BookmarksIOFunction {
   DECLARE_EXTENSION_FUNCTION("bookmarks.import", BOOKMARKS_IMPORT)
 
   // BookmarkManagerIOFunction:
-  virtual void FileSelected(const FilePath& path,
+  virtual void FileSelected(const base::FilePath& path,
                             int index,
                             void* params) OVERRIDE;
 
@@ -316,7 +315,7 @@ class BookmarksExportFunction : public BookmarksIOFunction {
   DECLARE_EXTENSION_FUNCTION("bookmarks.export", BOOKMARKS_EXPORT)
 
   // BookmarkManagerIOFunction:
-  virtual void FileSelected(const FilePath& path,
+  virtual void FileSelected(const base::FilePath& path,
                             int index,
                             void* params) OVERRIDE;
 
diff --git a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.h b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.h
index e18511e720782e..5062ab45c847f6 100644
--- a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.h
+++ b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_api.h
@@ -13,7 +13,6 @@
 #include "chrome/browser/extensions/extension_function.h"
 #include "chrome/browser/media_gallery/media_galleries_preferences.h"
 
-class FilePath;
 class Profile;
 
 namespace extensions {
diff --git a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.h b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.h
index b193faec372efb..b46543e8245ab5 100644
--- a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.h
+++ b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_event_router.h
@@ -19,7 +19,6 @@
 #include "chrome/browser/media_gallery/media_galleries_preferences.h"
 #include "chrome/browser/system_monitor/removable_storage_observer.h"
 
-class FilePath;
 class Profile;
 
 namespace base {
diff --git a/chrome/browser/extensions/api/messaging/native_process_launcher.h b/chrome/browser/extensions/api/messaging/native_process_launcher.h
index 41e735f1f1c0a9..cbb9bd37fc29bc 100644
--- a/chrome/browser/extensions/api/messaging/native_process_launcher.h
+++ b/chrome/browser/extensions/api/messaging/native_process_launcher.h
@@ -8,7 +8,9 @@
 #include "base/process.h"
 #include "chrome/browser/extensions/api/messaging/native_message_process_host.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace extensions {
 
@@ -35,7 +37,7 @@ class NativeProcessLauncher {
 
  protected:
   static bool LaunchNativeProcess(
-      const FilePath& path,
+      const base::FilePath& path,
       base::ProcessHandle* native_process_handle,
       base::PlatformFile* read_file,
       base::PlatformFile* write_file);
diff --git a/chrome/browser/extensions/api/page_capture/page_capture_api.h b/chrome/browser/extensions/api/page_capture/page_capture_api.h
index 4d7e80fffff624..e2d6ac42268abf 100644
--- a/chrome/browser/extensions/api/page_capture/page_capture_api.h
+++ b/chrome/browser/extensions/api/page_capture/page_capture_api.h
@@ -12,7 +12,9 @@
 #include "chrome/common/extensions/api/page_capture.h"
 #include "webkit/blob/shareable_file_reference.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 class WebContents;
@@ -29,7 +31,7 @@ class PageCaptureSaveAsMHTMLFunction : public AsyncExtensionFunction {
    public:
     // Called on the UI thread when the temporary file that contains the
     // generated data has been created.
-    virtual void OnTemporaryFileCreated(const FilePath& temp_file) = 0;
+    virtual void OnTemporaryFileCreated(const base::FilePath& temp_file) = 0;
   };
   static void SetTestDelegate(TestDelegate* delegate);
 
@@ -48,7 +50,7 @@ class PageCaptureSaveAsMHTMLFunction : public AsyncExtensionFunction {
   void ReturnSuccess(int64 file_size);
 
   // Callback called once the MHTML generation is done.
-  void MHTMLGenerated(const FilePath& file_path, int64 mhtml_file_size);
+  void MHTMLGenerated(const base::FilePath& file_path, int64 mhtml_file_size);
 
   // Returns the WebContents we are associated with, NULL if it's been closed.
   content::WebContents* GetWebContents();
@@ -56,7 +58,7 @@ class PageCaptureSaveAsMHTMLFunction : public AsyncExtensionFunction {
   scoped_ptr<extensions::api::page_capture::SaveAsMHTML::Params> params_;
 
   // The path to the temporary file containing the MHTML data.
-  FilePath mhtml_path_;
+  base::FilePath mhtml_path_;
 
   // The file containing the MHTML.
   scoped_refptr<webkit_blob::ShareableFileReference> mhtml_file_;
diff --git a/chrome/browser/extensions/api/storage/sync_or_local_value_store_cache.h b/chrome/browser/extensions/api/storage/sync_or_local_value_store_cache.h
index 8438b456b170db..64909ac83f786f 100644
--- a/chrome/browser/extensions/api/storage/sync_or_local_value_store_cache.h
+++ b/chrome/browser/extensions/api/storage/sync_or_local_value_store_cache.h
@@ -13,7 +13,9 @@
 #include "chrome/browser/extensions/api/storage/settings_storage_quota_enforcer.h"
 #include "chrome/browser/extensions/api/storage/value_store_cache.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace extensions {
 
@@ -30,7 +32,7 @@ class SyncOrLocalValueStoreCache : public ValueStoreCache {
       const scoped_refptr<SettingsStorageFactory>& factory,
       const SettingsStorageQuotaEnforcer::Limits& quota,
       const scoped_refptr<SettingsObserverList>& observers,
-      const FilePath& profile_path);
+      const base::FilePath& profile_path);
   virtual ~SyncOrLocalValueStoreCache();
 
   SettingsBackend* GetAppBackend() const;
@@ -48,7 +50,7 @@ class SyncOrLocalValueStoreCache : public ValueStoreCache {
   void InitOnFileThread(const scoped_refptr<SettingsStorageFactory>& factory,
                         const SettingsStorageQuotaEnforcer::Limits& quota,
                         const scoped_refptr<SettingsObserverList>& observers,
-                        const FilePath& profile_path);
+                        const base::FilePath& profile_path);
 
   settings_namespace::Namespace settings_namespace_;
   scoped_ptr<SettingsBackend> app_backend_;
diff --git a/chrome/browser/extensions/app_notification_manager.h b/chrome/browser/extensions/app_notification_manager.h
index 405b3492a2d7c0..4fa6e3096578da 100644
--- a/chrome/browser/extensions/app_notification_manager.h
+++ b/chrome/browser/extensions/app_notification_manager.h
@@ -119,7 +119,7 @@ class AppNotificationManager
   virtual ~AppNotificationManager();
 
   // Starts loading storage_ using |storage_path|.
-  void LoadOnFileThread(const FilePath& storage_path);
+  void LoadOnFileThread(const base::FilePath& storage_path);
 
   // Called on the UI thread to handle the loaded results from storage_.
   void HandleLoadResults(NotificationMap* map);
diff --git a/chrome/browser/extensions/app_notification_storage.h b/chrome/browser/extensions/app_notification_storage.h
index 1daf6b2d8a5cdb..5fda2fd44b0f06 100644
--- a/chrome/browser/extensions/app_notification_storage.h
+++ b/chrome/browser/extensions/app_notification_storage.h
@@ -9,7 +9,9 @@
 
 #include "chrome/browser/extensions/app_notification.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace extensions {
 
@@ -20,7 +22,7 @@ namespace extensions {
 class AppNotificationStorage {
  public:
   // Must be called on the FILE thread. The storage will be created at |path|.
-  static AppNotificationStorage* Create(const FilePath& path);
+  static AppNotificationStorage* Create(const base::FilePath& path);
 
   virtual ~AppNotificationStorage();
 
diff --git a/chrome/browser/extensions/convert_user_script.h b/chrome/browser/extensions/convert_user_script.h
index fa02f9048fed39..b5937773479b11 100644
--- a/chrome/browser/extensions/convert_user_script.h
+++ b/chrome/browser/extensions/convert_user_script.h
@@ -10,9 +10,12 @@
 #include "base/memory/ref_counted.h"
 #include "base/string16.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace extensions {
 class Extension;
 
@@ -24,8 +27,8 @@ class Extension;
 // NOTE: The caller takes ownership of the directory at extension->path() on the
 // returned object.
 scoped_refptr<extensions::Extension> ConvertUserScriptToExtension(
-    const FilePath& user_script, const GURL& original_url,
-    const FilePath& extensions_dir, string16* error);
+    const base::FilePath& user_script, const GURL& original_url,
+    const base::FilePath& extensions_dir, string16* error);
 
 }  // namespace extensions
 
diff --git a/chrome/browser/extensions/convert_web_app.h b/chrome/browser/extensions/convert_web_app.h
index 78d80f9d53a1e1..77c03d56de9537 100644
--- a/chrome/browser/extensions/convert_web_app.h
+++ b/chrome/browser/extensions/convert_web_app.h
@@ -9,9 +9,8 @@
 
 #include "base/memory/ref_counted.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -41,7 +40,7 @@ std::string ConvertTimeToExtensionVersion(const base::Time& time);
 scoped_refptr<Extension> ConvertWebAppToExtension(
     const WebApplicationInfo& web_app_info,
     const base::Time& create_time,
-    const FilePath& extensions_dir);
+    const base::FilePath& extensions_dir);
 
 }  // namespace extensions
 
diff --git a/chrome/browser/extensions/extension_apitest.h b/chrome/browser/extensions/extension_apitest.h
index 143f9fd2f2e10c..8d3d2e0ff3e39e 100644
--- a/chrome/browser/extensions/extension_apitest.h
+++ b/chrome/browser/extensions/extension_apitest.h
@@ -13,13 +13,14 @@
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "content/public/browser/notification_registrar.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace extensions {
 class Extension;
 }
 
-
 // The general flow of these API tests should work like this:
 // (1) Setup initial browser state (e.g. create some bookmarks for the
 //     bookmark test)
@@ -158,7 +159,7 @@ class ExtensionApiTest : public ExtensionBrowserTest {
   // Start the test WebSocket server, and store details of its state. Those
   // details will be available to javascript tests using
   // chrome.test.getConfig().
-  bool StartWebSocketServer(const FilePath& root_directory);
+  bool StartWebSocketServer(const base::FilePath& root_directory);
 
   // Test that exactly one extension loaded.  If so, return a pointer to
   // the extension.  If not, return NULL and set message_.
diff --git a/chrome/browser/extensions/extension_creator.h b/chrome/browser/extensions/extension_creator.h
index 86243ba164bcc7..de7aa7657e612d 100644
--- a/chrome/browser/extensions/extension_creator.h
+++ b/chrome/browser/extensions/extension_creator.h
@@ -10,12 +10,14 @@
 
 #include "base/basictypes.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace crypto {
 class RSAPrivateKey;
 }
 
-class FilePath;
-
 namespace extensions {
 
 // This class create an installable extension (.crx file) given an input
@@ -37,10 +39,10 @@ class ExtensionCreator {
   // Categories of error that may need special handling on the UI end.
   enum ErrorType { kOtherError, kCRXExists };
 
-  bool Run(const FilePath& extension_dir,
-           const FilePath& crx_path,
-           const FilePath& private_key_path,
-           const FilePath& private_key_output_path,
+  bool Run(const base::FilePath& extension_dir,
+           const base::FilePath& crx_path,
+           const base::FilePath& private_key_path,
+           const base::FilePath& private_key_output_path,
            int run_flags);
 
   // Returns the error message that will be present if Run(...) returned false.
@@ -56,38 +58,38 @@ class ExtensionCreator {
   // the extension. If not provided, a random key will be created (in which case
   // it is written to |private_key_output_path| -- if provided).
   // |flags| is a bitset of RunFlags values.
-  bool InitializeInput(const FilePath& extension_dir,
-                       const FilePath& crx_path,
-                       const FilePath& private_key_path,
-                       const FilePath& private_key_output_path,
+  bool InitializeInput(const base::FilePath& extension_dir,
+                       const base::FilePath& crx_path,
+                       const base::FilePath& private_key_path,
+                       const base::FilePath& private_key_output_path,
                        int run_flags);
 
   // Validates the manifest by trying to load the extension.
-  bool ValidateManifest(const FilePath& extension_dir,
+  bool ValidateManifest(const base::FilePath& extension_dir,
                         crypto::RSAPrivateKey* key_pair,
                         int run_flags);
 
   // Reads private key from |private_key_path|.
-  crypto::RSAPrivateKey* ReadInputKey(const FilePath& private_key_path);
+  crypto::RSAPrivateKey* ReadInputKey(const base::FilePath& private_key_path);
 
   // Generates a key pair and writes the private key to |private_key_path|
   // if provided.
-  crypto::RSAPrivateKey* GenerateKey(const FilePath& private_key_path);
+  crypto::RSAPrivateKey* GenerateKey(const base::FilePath& private_key_path);
 
   // Creates temporary zip file for the extension.
-  bool CreateZip(const FilePath& extension_dir, const FilePath& temp_path,
-                 FilePath* zip_path);
+  bool CreateZip(const base::FilePath& extension_dir, const base::FilePath& temp_path,
+                 base::FilePath* zip_path);
 
   // Signs the temporary zip and returns the signature.
-  bool SignZip(const FilePath& zip_path,
+  bool SignZip(const base::FilePath& zip_path,
                crypto::RSAPrivateKey* private_key,
                std::vector<uint8>* signature);
 
   // Export installable .crx to |crx_path|.
-  bool WriteCRX(const FilePath& zip_path,
+  bool WriteCRX(const base::FilePath& zip_path,
                 crypto::RSAPrivateKey* private_key,
                 const std::vector<uint8>& signature,
-                const FilePath& crx_path);
+                const base::FilePath& crx_path);
 
   // Holds a message for any error that is raised during Run(...).
   std::string error_message_;
diff --git a/chrome/browser/extensions/extension_creator_filter.h b/chrome/browser/extensions/extension_creator_filter.h
index c13e2c261b387b..6c0aac6d2b9e1d 100644
--- a/chrome/browser/extensions/extension_creator_filter.h
+++ b/chrome/browser/extensions/extension_creator_filter.h
@@ -7,7 +7,9 @@
 
 #include "base/memory/ref_counted.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace extensions {
 
@@ -18,9 +20,9 @@ class ExtensionCreatorFilter
  public:
   ExtensionCreatorFilter() {}
 
-  // Returns true if the given FilePath should be included in a
+  // Returns true if the given base::FilePath should be included in a
   // packed extension.
-  bool ShouldPackageFile(const FilePath& file_path);
+  bool ShouldPackageFile(const base::FilePath& file_path);
 
  private:
   friend class base::RefCounted<ExtensionCreatorFilter>;
diff --git a/chrome/browser/extensions/external_provider_interface.h b/chrome/browser/extensions/external_provider_interface.h
index 1d1f098e68f07e..20173864d4c840 100644
--- a/chrome/browser/extensions/external_provider_interface.h
+++ b/chrome/browser/extensions/external_provider_interface.h
@@ -10,10 +10,13 @@
 #include "base/memory/linked_ptr.h"
 #include "chrome/common/extensions/manifest.h"
 
-class FilePath;
 class GURL;
 class Version;
 
+namespace base {
+class FilePath;
+}
+
 namespace extensions {
 
 // This class is an abstract class for implementing external extensions
@@ -33,7 +36,7 @@ class ExternalProviderInterface {
     virtual bool OnExternalExtensionFileFound(
         const std::string& id,
         const Version* version,
-        const FilePath& path,
+        const base::FilePath& path,
         Manifest::Location location,
         int creation_flags,
         bool mark_acknowledged) = 0;
diff --git a/chrome/browser/extensions/platform_app_launcher.h b/chrome/browser/extensions/platform_app_launcher.h
index 96656412e696a2..ae9cfa53b8867b 100644
--- a/chrome/browser/extensions/platform_app_launcher.h
+++ b/chrome/browser/extensions/platform_app_launcher.h
@@ -8,9 +8,12 @@
 #include <string>
 
 class CommandLine;
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class WebContents;
 class WebIntentsDispatcher;
@@ -27,20 +30,20 @@ class Extension;
 void LaunchPlatformApp(Profile* profile,
                        const Extension* extension,
                        const CommandLine* command_line,
-                       const FilePath& current_directory);
+                       const base::FilePath& current_directory);
 
 // Launches the platform app |extension| with the contents of |file_path|
 // available through the launch data.
 void LaunchPlatformAppWithPath(Profile* profile,
                                const Extension* extension,
-                               const FilePath& file_path);
+                               const base::FilePath& file_path);
 
 // Launches the platform app |extension| with the contents of |file_path|
 // available through the launch data.
 void LaunchPlatformAppWithFileHandler(Profile* profile,
                                       const Extension* extension,
                                       const std::string& handler_id,
-                                      const FilePath& file_path);
+                                      const base::FilePath& file_path);
 
 #if defined(ENABLE_WEB_INTENTS)
 // Launches the platform app |extension| with the supplied web intent. Creates
diff --git a/chrome/browser/extensions/test_extension_system.h b/chrome/browser/extensions/test_extension_system.h
index 47faa2f0877614..d17ac0268f54a1 100644
--- a/chrome/browser/extensions/test_extension_system.h
+++ b/chrome/browser/extensions/test_extension_system.h
@@ -8,8 +8,9 @@
 #include "chrome/browser/extensions/extension_system.h"
 
 class CommandLine;
-class FilePath;
+
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -27,7 +28,7 @@ class TestExtensionSystem : public ExtensionSystem {
   // Creates an ExtensionService initialized with the testing profile and
   // returns it.
   ExtensionService* CreateExtensionService(const CommandLine* command_line,
-                                           const FilePath& install_directory,
+                                           const base::FilePath& install_directory,
                                            bool autoupdate_enabled);
 
   // Creates an ExtensionProcessManager. If not invoked, the
diff --git a/chrome/browser/extensions/updater/extension_downloader_delegate.h b/chrome/browser/extensions/updater/extension_downloader_delegate.h
index dd0b6c132ffd37..58e0dc95b25cd7 100644
--- a/chrome/browser/extensions/updater/extension_downloader_delegate.h
+++ b/chrome/browser/extensions/updater/extension_downloader_delegate.h
@@ -11,9 +11,12 @@
 #include "base/time.h"
 #include "chrome/browser/extensions/updater/manifest_fetch_data.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace extensions {
 
 class ExtensionDownloaderDelegate {
@@ -80,7 +83,7 @@ class ExtensionDownloaderDelegate {
   // to the delegate.
   virtual void OnExtensionDownloadFinished(
       const std::string& id,
-      const FilePath& path,
+      const base::FilePath& path,
       const GURL& download_url,
       const std::string& version,
       const PingResult& ping_result,
diff --git a/chrome/browser/extensions/webstore_installer.h b/chrome/browser/extensions/webstore_installer.h
index b263f81c2729ca..bda4aa0636d03c 100644
--- a/chrome/browser/extensions/webstore_installer.h
+++ b/chrome/browser/extensions/webstore_installer.h
@@ -21,9 +21,12 @@
 #include "googleurl/src/gurl.h"
 #include "net/base/net_errors.h"
 
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class NavigationController;
 }
@@ -142,7 +145,7 @@ class WebstoreInstaller :public content::NotificationObserver,
 
   // Instead of using the default download directory, use |directory| instead.
   // This does *not* transfer ownership of |directory|.
-  static void SetDownloadDirectoryForTests(FilePath* directory);
+  static void SetDownloadDirectoryForTests(base::FilePath* directory);
 
  private:
   friend struct content::BrowserThread::DeleteOnThread<
@@ -158,7 +161,7 @@ class WebstoreInstaller :public content::NotificationObserver,
   virtual void OnDownloadDestroyed(content::DownloadItem* download) OVERRIDE;
 
   // Starts downloading the extension to |file_path|.
-  void StartDownload(const FilePath& file_path);
+  void StartDownload(const base::FilePath& file_path);
 
   // Reports an install |error| to the delegate for the given extension if this
   // managed its installation. This also removes the associated PendingInstall.
diff --git a/chrome/browser/first_run/first_run.h b/chrome/browser/first_run/first_run.h
index 970cdd452e4dea..cf93bcf467b59e 100644
--- a/chrome/browser/first_run/first_run.h
+++ b/chrome/browser/first_run/first_run.h
@@ -17,12 +17,15 @@
 #include "ui/gfx/native_widget_types.h"
 
 class CommandLine;
-class FilePath;
 class GURL;
 class PrefServiceSyncable;
 class Profile;
 class ProcessSingleton;
 
+namespace base {
+class FilePath;
+}
+
 // This namespace contains the chrome first-run installation actions needed to
 // fully test the custom installer. It also contains the opposite actions to
 // execute during uninstall. When the first run UI is ready we won't
@@ -133,10 +136,10 @@ void DoPostImportTasks(Profile* profile, bool make_chrome_default);
 int ImportNow(Profile* profile, const CommandLine& cmdline);
 
 // Returns the path for the master preferences file.
-FilePath MasterPrefsPath();
+base::FilePath MasterPrefsPath();
 
 // Set a master preferences file path that overrides platform defaults.
-void SetMasterPrefsPathForTesting(const FilePath& master_prefs);
+void SetMasterPrefsPathForTesting(const base::FilePath& master_prefs);
 
 // The master preferences is a JSON file with the same entries as the
 // 'Default\Preferences' file. This function locates this file from a standard
@@ -152,7 +155,7 @@ void SetMasterPrefsPathForTesting(const FilePath& master_prefs);
 // See chrome/installer/util/master_preferences.h for a description of
 // 'master_preferences' file.
 ProcessMasterPreferencesResult ProcessMasterPreferences(
-    const FilePath& user_data_dir,
+    const base::FilePath& user_data_dir,
     MasterPrefs* out_prefs);
 
 // Show the first run search engine bubble at the first appropriate opportunity.
diff --git a/chrome/browser/first_run/first_run_internal.h b/chrome/browser/first_run/first_run_internal.h
index 9e56673d784559..7f8bd14383a673 100644
--- a/chrome/browser/first_run/first_run_internal.h
+++ b/chrome/browser/first_run/first_run_internal.h
@@ -14,7 +14,6 @@
 #include "ui/gfx/native_widget_types.h"
 
 class CommandLine;
-class FilePath;
 class GURL;
 class ImporterHost;
 class ImporterList;
@@ -22,6 +21,10 @@ class Profile;
 class ProcessSingleton;
 class TemplateURLService;
 
+namespace base {
+class FilePath;
+}
+
 namespace installer {
 class MasterPreferences;
 }
@@ -42,12 +45,12 @@ extern FirstRunState first_run_;
 // master preferences. Passes the master preference file path out in
 // master_prefs_path. Returns the pointer to installer::MasterPreferences object
 // if successful; otherwise, returns NULL.
-installer::MasterPreferences* LoadMasterPrefs(FilePath* master_prefs_path);
+installer::MasterPreferences* LoadMasterPrefs(base::FilePath* master_prefs_path);
 
 // Copies user preference file to master preference file. Returns true if
 // successful.
-bool CopyPrefFile(const FilePath& user_data_dir,
-                  const FilePath& master_prefs_path);
+bool CopyPrefFile(const base::FilePath& user_data_dir,
+                  const base::FilePath& master_prefs_path);
 
 // Sets up master preferences by preferences passed by installer.
 void SetupMasterPrefsFromInstallPrefs(
@@ -75,7 +78,7 @@ void DoPostImportPlatformSpecificTasks();
 // Gives the full path to the sentinel file. The file might not exist.
 // This function has a common implementation on OS_POSIX and a windows specific
 // implementation.
-bool GetFirstRunSentinelFilePath(FilePath* path);
+bool GetFirstRunSentinelFilePath(base::FilePath* path);
 
 // This function has a common implementationin for all non-linux platforms, and
 // a linux specific implementation.
@@ -100,7 +103,7 @@ int ImportBookmarkFromFileIfNeeded(Profile* profile,
                                    const CommandLine& cmdline);
 
 #if !defined(OS_WIN)
-bool ImportBookmarks(const FilePath& import_bookmarks_path);
+bool ImportBookmarks(const base::FilePath& import_bookmarks_path);
 #endif
 
 // Shows the EULA dialog if required. Returns true if the EULA is accepted,
diff --git a/chrome/browser/google_apis/drive_api_service.h b/chrome/browser/google_apis/drive_api_service.h
index 45876d1ca31db2..4da956832716b9 100644
--- a/chrome/browser/google_apis/drive_api_service.h
+++ b/chrome/browser/google_apis/drive_api_service.h
@@ -14,10 +14,13 @@
 #include "chrome/browser/google_apis/drive_api_url_generator.h"
 #include "chrome/browser/google_apis/drive_service_interface.h"
 
-class FilePath;
 class GURL;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace net {
 class URLRequestContextGetter;
 }  // namespace net
@@ -51,7 +54,7 @@ class DriveAPIService : public DriveServiceInterface,
   virtual void RemoveObserver(DriveServiceObserver* observer) OVERRIDE;
   virtual bool CanStartOperation() const OVERRIDE;
   virtual void CancelAll() OVERRIDE;
-  virtual bool CancelForFilePath(const FilePath& file_path) OVERRIDE;
+  virtual bool CancelForFilePath(const base::FilePath& file_path) OVERRIDE;
   virtual OperationProgressStatusList GetProgressStatusList() const OVERRIDE;
   virtual bool HasAccessToken() const OVERRIDE;
   virtual bool HasRefreshToken() const OVERRIDE;
@@ -74,8 +77,8 @@ class DriveAPIService : public DriveServiceInterface,
       const std::string& resource_id,
       const EntryActionCallback& callback) OVERRIDE;
   virtual void DownloadFile(
-      const FilePath& virtual_path,
-      const FilePath& local_cache_path,
+      const base::FilePath& virtual_path,
+      const base::FilePath& local_cache_path,
       const GURL& content_url,
       const DownloadActionCallback& download_action_callback,
       const GetContentCallback& get_content_callback) OVERRIDE;
diff --git a/chrome/browser/google_apis/drive_uploader.h b/chrome/browser/google_apis/drive_uploader.h
index c0007288e362c3..4dc496b47f681d 100644
--- a/chrome/browser/google_apis/drive_uploader.h
+++ b/chrome/browser/google_apis/drive_uploader.h
@@ -15,17 +15,20 @@
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 #include "chrome/browser/google_apis/gdata_wapi_parser.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace google_apis {
 class DriveServiceInterface;
 struct ResumeUploadResponse;
 
 // Callback to be invoked once the upload has completed.
 typedef base::Callback<void(DriveUploadError error,
-                            const FilePath& drive_path,
-                            const FilePath& file_path,
+                            const base::FilePath& drive_path,
+                            const base::FilePath& file_path,
                             scoped_ptr<ResourceEntry> resource_entry)>
     UploadCompletionCallback;
 
@@ -55,8 +58,8 @@ class DriveUploaderInterface {
   //   Called when an upload is done regardless of it was successful or not.
   //   Must not be null.
   virtual void UploadNewFile(const GURL& upload_location,
-                             const FilePath& drive_file_path,
-                             const FilePath& local_file_path,
+                             const base::FilePath& drive_file_path,
+                             const base::FilePath& local_file_path,
                              const std::string& title,
                              const std::string& content_type,
                              const UploadCompletionCallback& callback) = 0;
@@ -70,8 +73,8 @@ class DriveUploaderInterface {
   //   fails with UPLOAD_ERROR_CONFLICT.
   //   If |etag| is empty, the test is skipped.
   virtual void UploadExistingFile(const GURL& upload_location,
-                                  const FilePath& drive_file_path,
-                                  const FilePath& local_file_path,
+                                  const base::FilePath& drive_file_path,
+                                  const base::FilePath& local_file_path,
                                   const std::string& content_type,
                                   const std::string& etag,
                                   const UploadCompletionCallback& callback) = 0;
@@ -84,15 +87,15 @@ class DriveUploader : public DriveUploaderInterface {
 
   // DriveUploaderInterface overrides.
   virtual void UploadNewFile(const GURL& upload_location,
-                             const FilePath& drive_file_path,
-                             const FilePath& local_file_path,
+                             const base::FilePath& drive_file_path,
+                             const base::FilePath& local_file_path,
                              const std::string& title,
                              const std::string& content_type,
                              const UploadCompletionCallback& callback) OVERRIDE;
   virtual void UploadExistingFile(
       const GURL& upload_location,
-      const FilePath& drive_file_path,
-      const FilePath& local_file_path,
+      const base::FilePath& drive_file_path,
+      const base::FilePath& local_file_path,
       const std::string& content_type,
       const std::string& etag,
       const UploadCompletionCallback& callback) OVERRIDE;
diff --git a/chrome/browser/google_apis/gdata_wapi_parser.h b/chrome/browser/google_apis/gdata_wapi_parser.h
index 8f5c8f7275c5b7..2d973af2a6a049 100644
--- a/chrome/browser/google_apis/gdata_wapi_parser.h
+++ b/chrome/browser/google_apis/gdata_wapi_parser.h
@@ -17,12 +17,13 @@
 #include "chrome/browser/google_apis/drive_entry_kinds.h"
 #include "googleurl/src/gurl.h"
 
-class FilePath;
 class Profile;
 
 namespace base {
-class Value;
+class FilePath;
 class DictionaryValue;
+class Value;
+
 template <class StructType>
 class JSONValueConverter;
 
@@ -421,7 +422,7 @@ class ResourceEntry : public FeedEntry {
   static bool ParseChangestamp(const base::Value* value, int64* result);
 
   // Returns true if |file| has one of the hosted document extensions.
-  static bool HasHostedDocumentExtension(const FilePath& file);
+  static bool HasHostedDocumentExtension(const base::FilePath& file);
 
   // The resource ID is used to identify a resource, which looks like:
   // file:d41d8cd98f00b204e9800998ecf8
diff --git a/chrome/browser/google_apis/gdata_wapi_service.h b/chrome/browser/google_apis/gdata_wapi_service.h
index 2866a7c7089063..b454f2e8ebdb2f 100644
--- a/chrome/browser/google_apis/gdata_wapi_service.h
+++ b/chrome/browser/google_apis/gdata_wapi_service.h
@@ -15,10 +15,13 @@
 #include "chrome/browser/google_apis/gdata_wapi_operations.h"
 #include "chrome/browser/google_apis/gdata_wapi_url_generator.h"
 
-class FilePath;
 class GURL;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace net {
 class URLRequestContextGetter;
 }  // namespace net
@@ -55,7 +58,7 @@ class GDataWapiService : public DriveServiceInterface,
   virtual void RemoveObserver(DriveServiceObserver* observer) OVERRIDE;
   virtual bool CanStartOperation() const OVERRIDE;
   virtual void CancelAll() OVERRIDE;
-  virtual bool CancelForFilePath(const FilePath& file_path) OVERRIDE;
+  virtual bool CancelForFilePath(const base::FilePath& file_path) OVERRIDE;
   virtual OperationProgressStatusList GetProgressStatusList() const OVERRIDE;
   virtual bool HasAccessToken() const OVERRIDE;
   virtual bool HasRefreshToken() const OVERRIDE;
@@ -76,8 +79,8 @@ class GDataWapiService : public DriveServiceInterface,
   virtual void DeleteResource(const std::string& resource_id,
                               const EntryActionCallback& callback) OVERRIDE;
   virtual void DownloadFile(
-      const FilePath& virtual_path,
-      const FilePath& local_cache_path,
+      const base::FilePath& virtual_path,
+      const base::FilePath& local_cache_path,
       const GURL& content_url,
       const DownloadActionCallback& download_action_callback,
       const GetContentCallback& get_content_callback) OVERRIDE;
diff --git a/chrome/browser/google_apis/mock_drive_service.h b/chrome/browser/google_apis/mock_drive_service.h
index 42cbfe95ba2d07..eb8a9dc5bcc589 100644
--- a/chrome/browser/google_apis/mock_drive_service.h
+++ b/chrome/browser/google_apis/mock_drive_service.h
@@ -13,7 +13,9 @@
 #include "chrome/browser/google_apis/drive_service_interface.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace google_apis {
 
@@ -30,7 +32,7 @@ class MockDriveService : public DriveServiceInterface {
       void(DriveServiceObserver* observer));
   MOCK_CONST_METHOD0(CanStartOperation, bool());
   MOCK_METHOD0(CancelAll, void(void));
-  MOCK_METHOD1(CancelForFilePath, bool(const FilePath& file_path));
+  MOCK_METHOD1(CancelForFilePath, bool(const base::FilePath& file_path));
   MOCK_CONST_METHOD0(GetProgressStatusList,
       OperationProgressStatusList());
   MOCK_CONST_METHOD0(GetRootResourceId, std::string());
@@ -72,8 +74,8 @@ class MockDriveService : public DriveServiceInterface {
           const GetResourceEntryCallback& callback));
   MOCK_METHOD5(
       DownloadFile,
-      void(const FilePath& virtual_path,
-          const FilePath& local_cache_path,
+      void(const base::FilePath& virtual_path,
+          const base::FilePath& local_cache_path,
           const GURL& content_url,
           const DownloadActionCallback&
           donwload_action_callback,
@@ -151,8 +153,8 @@ class MockDriveService : public DriveServiceInterface {
   // portion of the URL as the temporary file path. If |file_data_| is not null,
   // |file_data_| is written to the temporary file.
   void DownloadFileStub(
-      const FilePath& virtual_path,
-      const FilePath& local_tmp_path,
+      const base::FilePath& virtual_path,
+      const base::FilePath& local_tmp_path,
       const GURL& content_url,
       const DownloadActionCallback& download_action_callback,
       const GetContentCallback& get_content_callback);
diff --git a/chrome/browser/google_apis/test_util.h b/chrome/browser/google_apis/test_util.h
index e0ba436be585ea..38a10517fd4169 100644
--- a/chrome/browser/google_apis/test_util.h
+++ b/chrome/browser/google_apis/test_util.h
@@ -11,9 +11,8 @@
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 #include "googleurl/src/gurl.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class Value;
 }
 
@@ -42,7 +41,7 @@ void RunBlockingPoolTask();
 
 // Returns the absolute path for a test file stored under
 // chrome/test/data/chromeos.
-FilePath GetTestFilePath(const std::string& relative_path);
+base::FilePath GetTestFilePath(const std::string& relative_path);
 
 // Returns the base URL for communicating with the local test server for
 // testing, running at the specified port number.
@@ -103,13 +102,13 @@ void CopyResultsFromGetAppListCallback(
 // Copies the results from DownloadActionCallback.
 void CopyResultsFromDownloadActionCallback(
     GDataErrorCode* error_out,
-    FilePath* temp_file_out,
+    base::FilePath* temp_file_out,
     GDataErrorCode error_in,
-    const FilePath& temp_file_in);
+    const base::FilePath& temp_file_in);
 
 // Returns a HttpResponse created from the given file path.
 scoped_ptr<test_server::HttpResponse> CreateHttpResponseFromFile(
-    const FilePath& file_path);
+    const base::FilePath& file_path);
 
 // Does nothing for ReAuthenticateCallback(). This function should be used
 // if it is not expected to reach this method as there won't be any
@@ -120,7 +119,7 @@ void DoNothingForReAuthenticateCallback(
 // Returns true if |json_data| is not NULL and equals to the content in
 // |expected_json_file_path|. The failure reason will be logged into LOG(ERROR)
 // if necessary.
-bool VerifyJsonData(const FilePath& expected_json_file_path,
+bool VerifyJsonData(const base::FilePath& expected_json_file_path,
                     const base::Value* json_data);
 
 }  // namespace test_util
diff --git a/chrome/browser/google_apis/time_util.h b/chrome/browser/google_apis/time_util.h
index f40aecc845f10a..222045b1ec2b43 100644
--- a/chrome/browser/google_apis/time_util.h
+++ b/chrome/browser/google_apis/time_util.h
@@ -9,7 +9,6 @@
 
 #include "base/string_piece.h"
 
-class FilePath;
 class Profile;
 
 namespace base {
diff --git a/chrome/browser/history/archived_database.cc b/chrome/browser/history/archived_database.cc
index 3eae2d6ae968f6..b80509ec7484d2 100644
--- a/chrome/browser/history/archived_database.cc
+++ b/chrome/browser/history/archived_database.cc
@@ -24,7 +24,7 @@ ArchivedDatabase::ArchivedDatabase() {
 ArchivedDatabase::~ArchivedDatabase() {
 }
 
-bool ArchivedDatabase::Init(const FilePath& file_name) {
+bool ArchivedDatabase::Init(const base::FilePath& file_name) {
   // Set the database page size to something a little larger to give us
   // better performance (we're typically seek rather than bandwidth limited).
   // This only has an effect before any tables have been created, otherwise
diff --git a/chrome/browser/history/archived_database.h b/chrome/browser/history/archived_database.h
index b157f66e74ce19..0fe7184acfc25a 100644
--- a/chrome/browser/history/archived_database.h
+++ b/chrome/browser/history/archived_database.h
@@ -12,7 +12,9 @@
 #include "sql/init_status.h"
 #include "sql/meta_table.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace history {
 
@@ -30,7 +32,7 @@ class ArchivedDatabase : public URLDatabase,
 
   // Initializes the database connection. This must return true before any other
   // functions on this class are called.
-  bool Init(const FilePath& file_name);
+  bool Init(const base::FilePath& file_name);
 
   // Transactions on the database. We support nested transactions and only
   // commit when the outermost one is committed (sqlite doesn't support true
diff --git a/chrome/browser/history/download_database.h b/chrome/browser/history/download_database.h
index 8cf07ab44b1c5a..929b097a6332ca 100644
--- a/chrome/browser/history/download_database.h
+++ b/chrome/browser/history/download_database.h
@@ -11,8 +11,6 @@
 #include "base/threading/platform_thread.h"
 #include "sql/meta_table.h"
 
-class FilePath;
-
 namespace sql {
 class Connection;
 }
diff --git a/chrome/browser/history/history_database.h b/chrome/browser/history/history_database.h
index b374260f16acc0..981c8a51c1a144 100644
--- a/chrome/browser/history/history_database.h
+++ b/chrome/browser/history/history_database.h
@@ -23,7 +23,9 @@
 #include "chrome/browser/history/android/android_urls_database.h"
 #endif
 
+namespace base {
 class FilePath;
+}
 
 namespace history {
 
@@ -67,7 +69,7 @@ class HistoryDatabase : public DownloadDatabase,
   // Must call this function to complete initialization. Will return
   // sql::INIT_OK on success. Otherwise, no other function should be called. You
   // may want to call BeginExclusiveMode after this when you are ready.
-  sql::InitStatus Init(const FilePath& history_name,
+  sql::InitStatus Init(const base::FilePath& history_name,
                        sql::ErrorDelegate* error_delegate);
 
   // Call to set the mode on the database to exclusive. The default locking mode
diff --git a/chrome/browser/history/history_service.h b/chrome/browser/history/history_service.h
index bd7307f507999d..c77878387d4f36 100644
--- a/chrome/browser/history/history_service.h
+++ b/chrome/browser/history/history_service.h
@@ -40,7 +40,6 @@
 #endif
 
 class BookmarkService;
-class FilePath;
 class GURL;
 class HistoryURLProvider;
 class PageUsageData;
@@ -49,6 +48,7 @@ class Profile;
 struct HistoryURLProviderParams;
 
 namespace base {
+class FilePath;
 class Thread;
 }
 
@@ -129,7 +129,7 @@ class HistoryService : public CancelableRequestProvider,
   // not call any other functions. The given directory will be used for storing
   // the history files. The BookmarkService is used when deleting URLs to
   // test if a URL is bookmarked; it may be NULL during testing.
-  bool Init(const FilePath& history_dir, BookmarkService* bookmark_service) {
+  bool Init(const base::FilePath& history_dir, BookmarkService* bookmark_service) {
     return Init(history_dir, bookmark_service, false);
   }
 
@@ -666,7 +666,7 @@ class HistoryService : public CancelableRequestProvider,
 
   // Low-level Init().  Same as the public version, but adds a |no_db| parameter
   // that is only set by unittests which causes the backend to not init its DB.
-  bool Init(const FilePath& history_dir,
+  bool Init(const base::FilePath& history_dir,
             BookmarkService* bookmark_service,
             bool no_db);
 
@@ -1094,7 +1094,7 @@ class HistoryService : public CancelableRequestProvider,
   int current_backend_id_;
 
   // Cached values from Init(), used whenever we need to reload the backend.
-  FilePath history_dir_;
+  base::FilePath history_dir_;
   BookmarkService* bookmark_service_;
   bool no_db_;
 
diff --git a/chrome/browser/history/in_memory_database.h b/chrome/browser/history/in_memory_database.h
index 17cb6f16e4d1e3..b729686389b135 100644
--- a/chrome/browser/history/in_memory_database.h
+++ b/chrome/browser/history/in_memory_database.h
@@ -9,7 +9,9 @@
 #include "chrome/browser/history/url_database.h"
 #include "sql/connection.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace history {
 
@@ -28,7 +30,7 @@ class InMemoryDatabase : public URLDatabase {
   // file. Conceptually, the InMemoryHistoryBackend should do the populating
   // after this object does some common initialization, but that would be
   // much slower.
-  bool InitFromDisk(const FilePath& history_name);
+  bool InitFromDisk(const base::FilePath& history_name);
 
  protected:
   // Implemented for URLDatabase.
diff --git a/chrome/browser/history/in_memory_history_backend.cc b/chrome/browser/history/in_memory_history_backend.cc
index b0dac72881ac88..f75d1c9ecf2b05 100644
--- a/chrome/browser/history/in_memory_history_backend.cc
+++ b/chrome/browser/history/in_memory_history_backend.cc
@@ -27,7 +27,7 @@ InMemoryHistoryBackend::InMemoryHistoryBackend()
 
 InMemoryHistoryBackend::~InMemoryHistoryBackend() {}
 
-bool InMemoryHistoryBackend::Init(const FilePath& history_filename,
+bool InMemoryHistoryBackend::Init(const base::FilePath& history_filename,
                                   URLDatabase* db) {
   db_.reset(new InMemoryDatabase);
   return db_->InitFromDisk(history_filename);
diff --git a/chrome/browser/history/in_memory_history_backend.h b/chrome/browser/history/in_memory_history_backend.h
index addfac95fd2e1a..a2d1f721e8d6ee 100644
--- a/chrome/browser/history/in_memory_history_backend.h
+++ b/chrome/browser/history/in_memory_history_backend.h
@@ -21,10 +21,13 @@
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
-class FilePath;
 class GURL;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace history {
 
 class InMemoryDatabase;
@@ -42,7 +45,7 @@ class InMemoryHistoryBackend : public content::NotificationObserver {
   // Initializes the backend from the history database pointed to by the
   // full path in |history_filename|. |db| is used for setting up the
   // InMemoryDatabase.
-  bool Init(const FilePath& history_filename, URLDatabase* db);
+  bool Init(const base::FilePath& history_filename, URLDatabase* db);
 
   // Does initialization work when this object is attached to the history
   // system on the main thread. The argument is the profile with which the
diff --git a/chrome/browser/history/thumbnail_database.h b/chrome/browser/history/thumbnail_database.h
index 9ee17c798b8ee4..4e8f7894d21fd3 100644
--- a/chrome/browser/history/thumbnail_database.h
+++ b/chrome/browser/history/thumbnail_database.h
@@ -15,11 +15,11 @@
 #include "sql/meta_table.h"
 #include "sql/statement.h"
 
-class FilePath;
 struct ThumbnailScore;
 class SkBitmap;
 
 namespace base {
+class FilePath;
 class RefCountedMemory;
 class Time;
 }
@@ -47,7 +47,7 @@ class ThumbnailDatabase {
 
   // Must be called after creation but before any other methods are called.
   // When not INIT_OK, no other functions should be called.
-  sql::InitStatus Init(const FilePath& db_name,
+  sql::InitStatus Init(const base::FilePath& db_name,
                        const HistoryPublisher* history_publisher,
                        URLDatabase* url_database);
 
@@ -56,7 +56,7 @@ class ThumbnailDatabase {
   // |db| is the database to open.
   // |db_name| is a path to the database file.
   static sql::InitStatus OpenDatabase(sql::Connection* db,
-                                      const FilePath& db_name);
+                                      const base::FilePath& db_name);
 
   // Transactions on the database.
   void BeginTransaction();
@@ -308,8 +308,8 @@ class ThumbnailDatabase {
   bool NeedsMigrationToTopSites();
 
   // Renames the database file and drops the Thumbnails table.
-  bool RenameAndDropThumbnails(const FilePath& old_db_file,
-                               const FilePath& new_db_file);
+  bool RenameAndDropThumbnails(const base::FilePath& old_db_file,
+                               const base::FilePath& new_db_file);
 
  private:
   friend class ExpireHistoryBackend;
diff --git a/chrome/browser/history/top_sites.h b/chrome/browser/history/top_sites.h
index e87f25d0940519..7ea4fa60f41e17 100644
--- a/chrome/browser/history/top_sites.h
+++ b/chrome/browser/history/top_sites.h
@@ -29,10 +29,10 @@
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/image/image.h"
 
-class FilePath;
 class Profile;
 
 namespace base {
+class FilePath;
 class RefCountedBytes;
 class RefCountedMemory;
 }
@@ -57,7 +57,7 @@ class TopSites
   explicit TopSites(Profile* profile);
 
   // Initializes TopSites.
-  void Init(const FilePath& db_name);
+  void Init(const base::FilePath& db_name);
 
   // Sets the given thumbnail for the given URL. Returns true if the thumbnail
   // was updated. False means either the URL wasn't known to us, or we felt
diff --git a/chrome/browser/history/top_sites_backend.h b/chrome/browser/history/top_sites_backend.h
index 163af2cea5707c..50282864a83b48 100644
--- a/chrome/browser/history/top_sites_backend.h
+++ b/chrome/browser/history/top_sites_backend.h
@@ -12,7 +12,10 @@
 #include "chrome/browser/history/history_types.h"
 
 class CancelableTaskTracker;
+
+namespace base {
 class FilePath;
+}
 
 namespace history {
 
@@ -31,7 +34,7 @@ class TopSitesBackend : public base::RefCountedThreadSafe<TopSitesBackend> {
 
   TopSitesBackend();
 
-  void Init(const FilePath& path);
+  void Init(const base::FilePath& path);
 
   // Schedules the db to be shutdown.
   void Shutdown();
@@ -64,7 +67,7 @@ class TopSitesBackend : public base::RefCountedThreadSafe<TopSitesBackend> {
   virtual ~TopSitesBackend();
 
   // Invokes Init on the db_.
-  void InitDBOnDBThread(const FilePath& path);
+  void InitDBOnDBThread(const base::FilePath& path);
 
   // Shuts down the db.
   void ShutdownDBOnDBThread();
@@ -83,9 +86,9 @@ class TopSitesBackend : public base::RefCountedThreadSafe<TopSitesBackend> {
                                   const Images& thumbnail);
 
   // Resets the database.
-  void ResetDatabaseOnDBThread(const FilePath& file_path);
+  void ResetDatabaseOnDBThread(const base::FilePath& file_path);
 
-  FilePath db_path_;
+  base::FilePath db_path_;
 
   scoped_ptr<TopSitesDatabase> db_;
 
diff --git a/chrome/browser/history/top_sites_database.h b/chrome/browser/history/top_sites_database.h
index 313c7063f9772b..42e04ed18cdfb9 100644
--- a/chrome/browser/history/top_sites_database.h
+++ b/chrome/browser/history/top_sites_database.h
@@ -13,7 +13,9 @@
 #include "chrome/browser/history/url_database.h"  // For DBCloseScoper.
 #include "sql/meta_table.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace sql {
 class Connection;
@@ -28,7 +30,7 @@ class TopSitesDatabase {
 
   // Must be called after creation but before any other methods are called.
   // Returns true on success. If false, no other functions should be called.
-  bool Init(const FilePath& db_name);
+  bool Init(const base::FilePath& db_name);
 
   // Returns true if migration of top sites from history may be needed. A value
   // of true means either migration is definitely needed (the top sites file is
@@ -92,7 +94,7 @@ class TopSitesDatabase {
   // Returns the number of URLs (rows) in the database.
   int GetRowCount();
 
-  sql::Connection* CreateDB(const FilePath& db_name);
+  sql::Connection* CreateDB(const base::FilePath& db_name);
 
   // Encodes redirects into a string.
   static std::string GetRedirects(const MostVisitedURL& url);
diff --git a/chrome/browser/icon_manager.h b/chrome/browser/icon_manager.h
index d6e17d43c29700..875c6d8ac15e77 100644
--- a/chrome/browser/icon_manager.h
+++ b/chrome/browser/icon_manager.h
@@ -51,7 +51,9 @@
 #include "chrome/common/cancelable_task_tracker.h"
 #include "ui/gfx/image/image.h"
 
+namespace base {
 class FilePath;
+}
 
 class IconManager : public IconLoader::Delegate {
  public:
@@ -63,7 +65,7 @@ class IconManager : public IconLoader::Delegate {
   // it via 'LoadIcon'. The returned bitmap is owned by the IconManager and must
   // not be free'd by the caller. If the caller needs to modify the icon, it
   // must make a copy and modify the copy.
-  gfx::Image* LookupIcon(const FilePath& file_name, IconLoader::IconSize size);
+  gfx::Image* LookupIcon(const base::FilePath& file_name, IconLoader::IconSize size);
 
   typedef base::Callback<void(gfx::Image*)> IconRequestCallback;
 
@@ -77,7 +79,7 @@ class IconManager : public IconLoader::Delegate {
   //    should never keep it or delete it.
   // 3. The gfx::Image pointer passed to the callback may be NULL if decoding
   //    failed.
-  CancelableTaskTracker::TaskId LoadIcon(const FilePath& file_name,
+  CancelableTaskTracker::TaskId LoadIcon(const base::FilePath& file_name,
                                          IconLoader::IconSize size,
                                          const IconRequestCallback& callback,
                                          CancelableTaskTracker* tracker);
@@ -87,7 +89,7 @@ class IconManager : public IconLoader::Delegate {
 
   // Get the identifying string for the given file. The implementation
   // is in icon_manager_[platform].cc.
-  static IconGroupID GetGroupIDFromFilepath(const FilePath& path);
+  static IconGroupID GetGroupIDFromFilepath(const base::FilePath& path);
 
  private:
   struct CacheKey {
diff --git a/chrome/browser/icon_manager_android.cc b/chrome/browser/icon_manager_android.cc
index 787d21cc42dec0..393af5e2904767 100644
--- a/chrome/browser/icon_manager_android.cc
+++ b/chrome/browser/icon_manager_android.cc
@@ -5,7 +5,7 @@
 #include "base/logging.h"
 #include "chrome/browser/icon_manager.h"
 
-IconGroupID IconManager::GetGroupIDFromFilepath(const FilePath& filepath) {
+IconGroupID IconManager::GetGroupIDFromFilepath(const base::FilePath& filepath) {
   NOTIMPLEMENTED();
   return 0;
 }
diff --git a/chrome/browser/icon_manager_linux.cc b/chrome/browser/icon_manager_linux.cc
index df7c62963fe6a9..5dfa1554fb5bb2 100644
--- a/chrome/browser/icon_manager_linux.cc
+++ b/chrome/browser/icon_manager_linux.cc
@@ -7,7 +7,8 @@
 #include "base/nix/mime_util_xdg.h"
 #include "base/threading/thread_restrictions.h"
 
-IconGroupID IconManager::GetGroupIDFromFilepath(const FilePath& filepath) {
+IconGroupID IconManager::GetGroupIDFromFilepath(
+    const base::FilePath& filepath) {
   // It turns out the call to base::nix::GetFileMimeType below does IO, but
   // callers of GetGroupIDFromFilepath assume it does not do IO (the Windows
   // and Mac implementations do not). We should fix this by either not doing IO
diff --git a/chrome/browser/importer/firefox_importer_utils.h b/chrome/browser/importer/firefox_importer_utils.h
index 1ba9bfe7c48259..f723ba4a8a41e0 100644
--- a/chrome/browser/importer/firefox_importer_utils.h
+++ b/chrome/browser/importer/firefox_importer_utils.h
@@ -12,12 +12,12 @@
 #include "base/string16.h"
 #include "build/build_config.h"
 
-class FilePath;
 class GURL;
 class TemplateURL;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 #if defined(OS_WIN)
@@ -29,7 +29,7 @@ int GetCurrentFirefoxMajorVersionFromRegistry();
 
 // Detects where Firefox lives. Returns an empty path if Firefox is not
 // installed.
-FilePath GetFirefoxInstallPathFromRegistry();
+base::FilePath GetFirefoxInstallPathFromRegistry();
 #endif  // OS_WIN
 
 #if defined(OS_MACOSX)
@@ -37,21 +37,21 @@ FilePath GetFirefoxInstallPathFromRegistry();
 // in order to decoded FF profile passwords.
 // The Path is usuall FF App Bundle/Contents/Mac OS/
 // Returns empty path on failure.
-FilePath GetFirefoxDylibPath();
+base::FilePath GetFirefoxDylibPath();
 #endif  // OS_MACOSX
 
 // Returns the path to the Firefox profile.
-FilePath GetFirefoxProfilePath();
+base::FilePath GetFirefoxProfilePath();
 
 // Detects version of Firefox and installation path for the given Firefox
 // profile.
-bool GetFirefoxVersionAndPathFromProfile(const FilePath& profile_path,
+bool GetFirefoxVersionAndPathFromProfile(const base::FilePath& profile_path,
                                          int* version,
-                                         FilePath* app_path);
+                                         base::FilePath* app_path);
 
 // Gets the full path of the profiles.ini file. This file records the profiles
 // that can be used by Firefox. Returns an empty path if failed.
-FilePath GetProfilesINI();
+base::FilePath GetProfilesINI();
 
 // Parses the profile.ini file, and stores its information in |root|.
 // This file is a plain-text file. Key/value pairs are stored one per line, and
@@ -65,7 +65,7 @@ FilePath GetProfilesINI();
 //   Path=Profiles/abcdefeg.default
 // We set "[value]" in path "<Section>.<Key>". For example, the path
 // "Genenral.StartWithLastProfile" has the value "1".
-void ParseProfileINI(const FilePath& file, base::DictionaryValue* root);
+void ParseProfileINI(const base::FilePath& file, base::DictionaryValue* root);
 
 // Returns true if we want to add the URL to the history. We filter out the URL
 // with a unsupported scheme.
@@ -73,16 +73,16 @@ bool CanImportURL(const GURL& url);
 
 // Parses the OpenSearch XML files in |xml_files| and populates |search_engines|
 // with the resulting TemplateURLs.
-void ParseSearchEnginesFromXMLFiles(const std::vector<FilePath>& xml_files,
+void ParseSearchEnginesFromXMLFiles(const std::vector<base::FilePath>& xml_files,
                                     std::vector<TemplateURL*>* search_engines);
 
 // Returns the home page set in Firefox in a particular profile.
-GURL GetHomepage(const FilePath& profile_path);
+GURL GetHomepage(const base::FilePath& profile_path);
 
 // Checks to see if this home page is a default home page, as specified by
 // the resource file browserconfig.properties in the Firefox application
 // directory.
-bool IsDefaultHomepage(const GURL& homepage, const FilePath& app_path);
+bool IsDefaultHomepage(const GURL& homepage, const base::FilePath& app_path);
 
 // Parses the prefs found in the file |pref_file| and puts the key/value pairs
 // in |prefs|. Keys are strings, and values can be strings, booleans or
@@ -90,7 +90,7 @@ bool IsDefaultHomepage(const GURL& homepage, const FilePath& app_path);
 // |prefs| is not filled).
 // Note: for strings, only valid UTF-8 string values are supported. If a
 // key/pair is not valid UTF-8, it is ignored and will not appear in |prefs|.
-bool ParsePrefFile(const FilePath& pref_file, base::DictionaryValue* prefs);
+bool ParsePrefFile(const base::FilePath& pref_file, base::DictionaryValue* prefs);
 
 // Parses the value of a particular firefox preference from a string that is the
 // contents of the prefs file.
@@ -101,6 +101,6 @@ std::string GetPrefsJsValue(const std::string& prefs,
 // This is useful to differentiate between Firefox and Iceweasel.
 // If anything goes wrong while trying to obtain the branding name,
 // the function assumes it's Firefox.
-string16 GetFirefoxImporterName(const FilePath& app_path);
+string16 GetFirefoxImporterName(const base::FilePath& app_path);
 
 #endif  // CHROME_BROWSER_IMPORTER_FIREFOX_IMPORTER_UTILS_H_
diff --git a/chrome/browser/importer/firefox_proxy_settings.h b/chrome/browser/importer/firefox_proxy_settings.h
index 6f7449459545c1..41657a27dffcb1 100644
--- a/chrome/browser/importer/firefox_proxy_settings.h
+++ b/chrome/browser/importer/firefox_proxy_settings.h
@@ -10,7 +10,9 @@
 
 #include "base/basictypes.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace net {
 class ProxyConfig;
@@ -78,7 +80,7 @@ class FirefoxProxySettings {
   // Gets the settings from the passed prefs.js file and returns true if
   // successful.
   // Protected for tests.
-  static bool GetSettingsFromFile(const FilePath& pref_file,
+  static bool GetSettingsFromFile(const base::FilePath& pref_file,
                                   FirefoxProxySettings* settings);
 
  private:
diff --git a/chrome/browser/importer/mork_reader.h b/chrome/browser/importer/mork_reader.h
index d139477c333bc8..05eed2c0b617d4 100644
--- a/chrome/browser/importer/mork_reader.h
+++ b/chrome/browser/importer/mork_reader.h
@@ -49,9 +49,12 @@
 
 #include "base/basictypes.h"
 
-class FilePath;
 class ImporterBridge;
 
+namespace base {
+class FilePath;
+}
+
 // The nsMorkReader object allows a consumer to read in a mork-format
 // file and enumerate the rows that it contains.  It does not provide
 // any functionality for modifying mork tables.
@@ -90,7 +93,7 @@ class MorkReader {
 
   // Read in the given mork file. Returns true on success.
   // Note: currently, only single-table mork files are supported
-  bool Read(const FilePath& filename);
+  bool Read(const base::FilePath& filename);
 
   // Returns the list of columns in the current table.
   const MorkColumnList& columns() const { return columns_; }
@@ -158,6 +161,6 @@ class MorkReader {
 };
 
 // ImportHistoryFromFirefox2 is the main entry point to the importer.
-void ImportHistoryFromFirefox2(const FilePath& file, ImporterBridge* bridge);
+void ImportHistoryFromFirefox2(const base::FilePath& file, ImporterBridge* bridge);
 
 #endif  // CHROME_BROWSER_IMPORTER_MORK_READER_H_
diff --git a/chrome/browser/importer/nss_decryptor.cc b/chrome/browser/importer/nss_decryptor.cc
index 44398137170e19..7a00b35036ab50 100644
--- a/chrome/browser/importer/nss_decryptor.cc
+++ b/chrome/browser/importer/nss_decryptor.cc
@@ -232,7 +232,7 @@ void NSSDecryptor::ParseSignons(
   }
 }
 
-bool NSSDecryptor::ReadAndParseSignons(const FilePath& sqlite_file,
+bool NSSDecryptor::ReadAndParseSignons(const base::FilePath& sqlite_file,
     std::vector<content::PasswordForm>* forms) {
   sql::Connection db;
   if (!db.Open(sqlite_file))
diff --git a/chrome/browser/importer/nss_decryptor_mac.h b/chrome/browser/importer/nss_decryptor_mac.h
index 7cae82e960d86b..e8c7857546a04b 100644
--- a/chrome/browser/importer/nss_decryptor_mac.h
+++ b/chrome/browser/importer/nss_decryptor_mac.h
@@ -11,7 +11,9 @@
 #include "base/basictypes.h"
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 // The following declarations of functions and types are from Firefox
 // NSS library.
@@ -120,7 +122,7 @@ class NSSDecryptor {
   ~NSSDecryptor();
 
   // Initializes NSS if it hasn't already been initialized.
-  bool Init(const FilePath& dll_path, const FilePath& db_path);
+  bool Init(const base::FilePath& dll_path, const base::FilePath& db_path);
 
   // Decrypts Firefox stored passwords. Before using this method,
   // make sure Init() returns true.
@@ -135,7 +137,7 @@ class NSSDecryptor {
   // Reads and parses the Firefox password sqlite db, decrypts the
   // username/password and reads other related information.
   // The result will be stored in |forms|.
-  bool ReadAndParseSignons(const FilePath& sqlite_file,
+  bool ReadAndParseSignons(const base::FilePath& sqlite_file,
                            std::vector<content::PasswordForm>* forms);
  private:
   PK11SlotInfo* GetKeySlotForDB() const { return PK11_GetInternalKeySlot(); }
diff --git a/chrome/browser/importer/nss_decryptor_null.h b/chrome/browser/importer/nss_decryptor_null.h
index 4fd6934534842f..5e690f4544dbf0 100644
--- a/chrome/browser/importer/nss_decryptor_null.h
+++ b/chrome/browser/importer/nss_decryptor_null.h
@@ -11,7 +11,9 @@
 #include "base/basictypes.h"
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 struct PasswordForm;
@@ -22,11 +24,11 @@ struct PasswordForm;
 class NSSDecryptor {
  public:
   NSSDecryptor() {}
-  bool Init(const FilePath& dll_path, const FilePath& db_path) { return false; }
+  bool Init(const base::FilePath& dll_path, const base::FilePath& db_path) { return false; }
   string16 Decrypt(const std::string& crypt) const { return string16(); }
   void ParseSignons(const std::string& content,
                     std::vector<content::PasswordForm>* forms) {}
-  bool ReadAndParseSignons(const FilePath& sqlite_file,
+  bool ReadAndParseSignons(const base::FilePath& sqlite_file,
                            std::vector<content::PasswordForm>* forms) {
     return false;
   }
diff --git a/chrome/browser/importer/nss_decryptor_system_nss.h b/chrome/browser/importer/nss_decryptor_system_nss.h
index c125da964c252c..41c422763d6ad1 100644
--- a/chrome/browser/importer/nss_decryptor_system_nss.h
+++ b/chrome/browser/importer/nss_decryptor_system_nss.h
@@ -12,7 +12,9 @@
 #include "base/basictypes.h"
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 struct PasswordForm;
@@ -25,7 +27,7 @@ class NSSDecryptor {
   ~NSSDecryptor();
 
   // Initializes NSS if it hasn't already been initialized.
-  bool Init(const FilePath& dll_path, const FilePath& db_path);
+  bool Init(const base::FilePath& dll_path, const base::FilePath& db_path);
 
   // Decrypts Firefox stored passwords. Before using this method,
   // make sure Init() returns true.
@@ -40,7 +42,7 @@ class NSSDecryptor {
   // Reads and parses the Firefox password sqlite db, decrypts the
   // username/password and reads other related information.
   // The result will be stored in |forms|.
-  bool ReadAndParseSignons(const FilePath& sqlite_file,
+  bool ReadAndParseSignons(const base::FilePath& sqlite_file,
                            std::vector<content::PasswordForm>* forms);
  private:
   // Does not actually free the slot, since we'll free it when NSSDecryptor is
diff --git a/chrome/browser/importer/nss_decryptor_win.h b/chrome/browser/importer/nss_decryptor_win.h
index 1aeb266d65406a..0a7b5ba7efa0cc 100644
--- a/chrome/browser/importer/nss_decryptor_win.h
+++ b/chrome/browser/importer/nss_decryptor_win.h
@@ -117,7 +117,7 @@ class NSSDecryptor {
   // Loads NSS3 library and returns true if successful.
   // |dll_path| indicates the location of NSS3 DLL files, and |db_path|
   // is the location of the database file that stores the keys.
-  bool Init(const FilePath& dll_path, const FilePath& db_path);
+  bool Init(const base::FilePath& dll_path, const base::FilePath& db_path);
 
   // Frees the libraries.
   void Free();
@@ -135,12 +135,12 @@ class NSSDecryptor {
   // Reads and parses the Firefox password sqlite db, decrypts the
   // username/password and reads other related information.
   // The result will be stored in |forms|.
-  bool ReadAndParseSignons(const FilePath& sqlite_file,
+  bool ReadAndParseSignons(const base::FilePath& sqlite_file,
                            std::vector<content::PasswordForm>* forms);
 
  private:
   // Call NSS initialization funcs.
-  bool InitNSS(const FilePath& db_path,
+  bool InitNSS(const base::FilePath& db_path,
                base::NativeLibrary plds4_dll,
                base::NativeLibrary nspr4_dll);
 
diff --git a/chrome/browser/jumplist_win.h b/chrome/browser/jumplist_win.h
index 401b5417fb042b..d4865ab949c56e 100644
--- a/chrome/browser/jumplist_win.h
+++ b/chrome/browser/jumplist_win.h
@@ -21,10 +21,14 @@
 #include "content/public/browser/browser_thread.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class NotificationRegistrar;
 }
-class FilePath;
+
 class Profile;
 class PageUsageData;
 
@@ -222,7 +226,7 @@ class JumpList : public TabRestoreServiceObserver,
   std::wstring app_id_;
 
   // The directory which contains JumpList icons.
-  FilePath icon_dir_;
+  base::FilePath icon_dir_;
 
   // Items in the "Most Visited" category of the application JumpList,
   // protected by the list_lock_.
diff --git a/chrome/browser/managed_mode/managed_mode_url_filter.h b/chrome/browser/managed_mode/managed_mode_url_filter.h
index 875b64f61aa90d..2059cb4e410128 100644
--- a/chrome/browser/managed_mode/managed_mode_url_filter.h
+++ b/chrome/browser/managed_mode/managed_mode_url_filter.h
@@ -19,7 +19,6 @@ namespace policy {
 class URLBlacklist;
 }  // namespace policy
 
-class FilePath;
 class GURL;
 
 // This class manages the filtering behavior for a given URL, i.e. it tells
diff --git a/chrome/browser/media_gallery/linux/mtp_device_delegate_impl_linux.h b/chrome/browser/media_gallery/linux/mtp_device_delegate_impl_linux.h
index bf98cbcfbebd98..fff71103abbeb4 100644
--- a/chrome/browser/media_gallery/linux/mtp_device_delegate_impl_linux.h
+++ b/chrome/browser/media_gallery/linux/mtp_device_delegate_impl_linux.h
@@ -15,9 +15,8 @@
 #include "webkit/fileapi/file_system_file_util.h"
 #include "webkit/fileapi/media/mtp_device_delegate.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }
 
@@ -52,14 +51,14 @@ class MTPDeviceDelegateImplLinux : public fileapi::MTPDeviceDelegate {
 
   // MTPDeviceDelegate:
   virtual base::PlatformFileError GetFileInfo(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       base::PlatformFileInfo* file_info) OVERRIDE;
   virtual scoped_ptr<fileapi::FileSystemFileUtil::AbstractFileEnumerator>
-      CreateFileEnumerator(const FilePath& root,
+      CreateFileEnumerator(const base::FilePath& root,
                            bool recursive) OVERRIDE;
   virtual base::PlatformFileError CreateSnapshotFile(
-      const FilePath& device_file_path,
-      const FilePath& local_path,
+      const base::FilePath& device_file_path,
+      const base::FilePath& local_path,
       base::PlatformFileInfo* file_info) OVERRIDE;
   virtual void CancelPendingTasksAndDeleteDelegate() OVERRIDE;
 
diff --git a/chrome/browser/media_gallery/media_file_system_context.h b/chrome/browser/media_gallery/media_file_system_context.h
index 09259908ffbfad..17147329770822 100644
--- a/chrome/browser/media_gallery/media_file_system_context.h
+++ b/chrome/browser/media_gallery/media_file_system_context.h
@@ -13,7 +13,9 @@
 #include "chrome/browser/media_gallery/scoped_mtp_device_map_entry.h"
 #include "webkit/fileapi/media/mtp_device_file_system_config.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
@@ -26,14 +28,14 @@ class MediaFileSystemContext {
   // Register a media file system (filtered to media files) for |path| and
   // return the new file system id.
   virtual std::string RegisterFileSystemForMassStorage(
-      const std::string& device_id, const FilePath& path) = 0;
+      const std::string& device_id, const base::FilePath& path) = 0;
 
 #if defined(SUPPORT_MTP_DEVICE_FILESYSTEM)
   // Registers and returns the file system id for the MTP or PTP device
   // specified by |device_id| and |path|. Updates |entry| with the corresponding
   // ScopedMTPDeviceMapEntry object.
   virtual std::string RegisterFileSystemForMTPDevice(
-      const std::string& device_id, const FilePath& path,
+      const std::string& device_id, const base::FilePath& path,
       scoped_refptr<ScopedMTPDeviceMapEntry>* entry) = 0;
 #endif
 
diff --git a/chrome/browser/media_gallery/win/mtp_device_delegate_impl_win.h b/chrome/browser/media_gallery/win/mtp_device_delegate_impl_win.h
index db41cf0c732006..d439edd874f654 100644
--- a/chrome/browser/media_gallery/win/mtp_device_delegate_impl_win.h
+++ b/chrome/browser/media_gallery/win/mtp_device_delegate_impl_win.h
@@ -18,9 +18,8 @@
 #include "webkit/fileapi/file_system_file_util.h"
 #include "webkit/fileapi/media/mtp_device_delegate.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }
 
@@ -56,14 +55,14 @@ class MTPDeviceDelegateImplWin : public fileapi::MTPDeviceDelegate {
 
   // MTPDeviceDelegate:
   virtual base::PlatformFileError GetFileInfo(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       base::PlatformFileInfo* file_info) OVERRIDE;
   virtual scoped_ptr<fileapi::FileSystemFileUtil::AbstractFileEnumerator>
-      CreateFileEnumerator(const FilePath& root,
+      CreateFileEnumerator(const base::FilePath& root,
                            bool recursive) OVERRIDE;
   virtual base::PlatformFileError CreateSnapshotFile(
-      const FilePath& device_file_path,
-      const FilePath& local_path,
+      const base::FilePath& device_file_path,
+      const base::FilePath& local_path,
       base::PlatformFileInfo* file_info) OVERRIDE;
   virtual void CancelPendingTasksAndDeleteDelegate() OVERRIDE;
 
diff --git a/chrome/browser/media_gallery/win/recursive_mtp_device_object_enumerator.h b/chrome/browser/media_gallery/win/recursive_mtp_device_object_enumerator.h
index 7c7d991a4da8a3..8cf6a6b9456ef7 100644
--- a/chrome/browser/media_gallery/win/recursive_mtp_device_object_enumerator.h
+++ b/chrome/browser/media_gallery/win/recursive_mtp_device_object_enumerator.h
@@ -18,7 +18,9 @@
 #include "chrome/browser/media_gallery/win/mtp_device_object_entry.h"
 #include "webkit/fileapi/file_system_file_util.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
@@ -40,7 +42,7 @@ class RecursiveMTPDeviceObjectEnumerator
   virtual ~RecursiveMTPDeviceObjectEnumerator();
 
   // AbstractFileEnumerator:
-  virtual FilePath Next() OVERRIDE;
+  virtual base::FilePath Next() OVERRIDE;
   virtual int64 Size() OVERRIDE;
   virtual bool IsDirectory() OVERRIDE;
   virtual base::Time LastModifiedTime() OVERRIDE;
diff --git a/chrome/browser/nacl_host/pnacl_file_host.h b/chrome/browser/nacl_host/pnacl_file_host.h
index 71875610dd4d80..f1a31bd9aeb344 100644
--- a/chrome/browser/nacl_host/pnacl_file_host.h
+++ b/chrome/browser/nacl_host/pnacl_file_host.h
@@ -8,7 +8,10 @@
 #include <string>
 
 class ChromeRenderMessageFilter;
+
+namespace base {
 class FilePath;
+}
 
 namespace IPC {
 class Message;
@@ -24,9 +27,9 @@ void GetReadonlyPnaclFd(ChromeRenderMessageFilter* chrome_render_message_filter,
                         IPC::Message* reply_msg);
 
 // Return true if the filename requested is valid for opening.
-// Sets file_to_open to the FilePath which we will attempt to open.
+// Sets file_to_open to the base::FilePath which we will attempt to open.
 bool PnaclCanOpenFile(const std::string& filename,
-                      FilePath* file_to_open);
+                      base::FilePath* file_to_open);
 
 // Creates a temporary file that will be deleted when the last handle
 // is closed, or earlier.
diff --git a/chrome/browser/net/chrome_network_delegate.h b/chrome/browser/net/chrome_network_delegate.h
index 90e7a75a800234..85bfd0fbb06334 100644
--- a/chrome/browser/net/chrome_network_delegate.h
+++ b/chrome/browser/net/chrome_network_delegate.h
@@ -154,7 +154,7 @@ class ChromeNetworkDelegate : public net::NetworkDelegate {
                               const std::string& cookie_line,
                               net::CookieOptions* options) OVERRIDE;
   virtual bool OnCanAccessFile(const net::URLRequest& request,
-                               const FilePath& path) const OVERRIDE;
+                               const base::FilePath& path) const OVERRIDE;
   virtual bool OnCanThrottleRequest(
       const net::URLRequest& request) const OVERRIDE;
   virtual int OnBeforeSocketStreamConnect(
diff --git a/chrome/browser/net/crl_set_fetcher.cc b/chrome/browser/net/crl_set_fetcher.cc
index 66302850dca4ea..9c869b37e2349d 100644
--- a/chrome/browser/net/crl_set_fetcher.cc
+++ b/chrome/browser/net/crl_set_fetcher.cc
@@ -22,7 +22,7 @@ using content::BrowserThread;
 
 CRLSetFetcher::CRLSetFetcher() : cus_(NULL) {}
 
-bool CRLSetFetcher::GetCRLSetFilePath(FilePath* path) const {
+bool CRLSetFetcher::GetCRLSetFilePath(base::FilePath* path) const {
   bool ok = PathService::Get(chrome::DIR_USER_DATA, path);
   if (!ok) {
     NOTREACHED();
@@ -47,7 +47,7 @@ void CRLSetFetcher::StartInitialLoad(ComponentUpdateService* cus) {
 void CRLSetFetcher::DoInitialLoadFromDisk() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
-  FilePath crl_set_file_path;
+  base::FilePath crl_set_file_path;
   if (!GetCRLSetFilePath(&crl_set_file_path))
     return;
 
@@ -69,7 +69,7 @@ void CRLSetFetcher::DoInitialLoadFromDisk() {
   }
 }
 
-void CRLSetFetcher::LoadFromDisk(FilePath path,
+void CRLSetFetcher::LoadFromDisk(base::FilePath path,
                                  scoped_refptr<net::CRLSet>* out_crl_set) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
@@ -143,11 +143,12 @@ void CRLSetFetcher::OnUpdateError(int error) {
 }
 
 bool CRLSetFetcher::Install(base::DictionaryValue* manifest,
-                            const FilePath& unpack_path) {
+                            const base::FilePath& unpack_path) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
-  FilePath crl_set_file_path = unpack_path.Append(FILE_PATH_LITERAL("crl-set"));
-  FilePath save_to;
+  base::FilePath crl_set_file_path =
+      unpack_path.Append(FILE_PATH_LITERAL("crl-set"));
+  base::FilePath save_to;
   if (!GetCRLSetFilePath(&save_to))
     return true;
 
diff --git a/chrome/browser/net/crl_set_fetcher.h b/chrome/browser/net/crl_set_fetcher.h
index 86dd8ee3b0c775..8bcca1ff021486 100644
--- a/chrome/browser/net/crl_set_fetcher.h
+++ b/chrome/browser/net/crl_set_fetcher.h
@@ -11,10 +11,9 @@
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/component_updater/component_updater_service.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace net {
@@ -33,16 +32,16 @@ class CRLSetFetcher : public ComponentInstaller,
   // ComponentInstaller interface
   virtual void OnUpdateError(int error) OVERRIDE;
   virtual bool Install(base::DictionaryValue* manifest,
-                       const FilePath& unpack_path) OVERRIDE;
+                       const base::FilePath& unpack_path) OVERRIDE;
 
  private:
   friend class base::RefCountedThreadSafe<CRLSetFetcher>;
 
   virtual ~CRLSetFetcher();
 
-  // GetCRLSetFilePath gets the path of the CRL set file in the user data
+  // GetCRLSetbase::FilePath gets the path of the CRL set file in the user data
   // dir.
-  bool GetCRLSetFilePath(FilePath* path) const;
+  bool GetCRLSetFilePath(base::FilePath* path) const;
 
   // DoInitialLoadFromDisk runs on the FILE thread and attempts to load a CRL
   // set from the user-data dir. It then registers this object as a component
@@ -51,7 +50,7 @@ class CRLSetFetcher : public ComponentInstaller,
 
   // LoadFromDisk runs on the FILE thread and attempts to load a CRL set
   // from |load_from|.
-  void LoadFromDisk(FilePath load_from,
+  void LoadFromDisk(base::FilePath load_from,
                     scoped_refptr<net::CRLSet>* out_crl_set);
 
   // SetCRLSetIfNewer runs on the IO thread and installs a CRL set
diff --git a/chrome/browser/net/net_log_logger.h b/chrome/browser/net/net_log_logger.h
index e8505b157e8eb1..33e821746f47ab 100644
--- a/chrome/browser/net/net_log_logger.h
+++ b/chrome/browser/net/net_log_logger.h
@@ -8,7 +8,9 @@
 #include "base/memory/scoped_handle.h"
 #include "net/base/net_log.h"
 
+namespace base {
 class FilePath;
+}
 
 // NetLogLogger watches the NetLog event stream, and sends all entries to
 // VLOG(1) or a path specified on creation.  This is to debug errors that
@@ -25,7 +27,7 @@ class NetLogLogger : public net::NetLog::ThreadSafeObserver {
   // If |log_path| is empty or file creation fails, writes to VLOG(1).
   // Otherwise, writes to |log_path|.  Uses one line per entry, for
   // easy parsing.
-  explicit NetLogLogger(const FilePath &log_path);
+  explicit NetLogLogger(const base::FilePath &log_path);
   virtual ~NetLogLogger();
 
   // Starts observing specified NetLog.  Must not already be watching a NetLog.
diff --git a/chrome/browser/net/sqlite_persistent_cookie_store.h b/chrome/browser/net/sqlite_persistent_cookie_store.h
index 72675da44e003a..bb6206d8f211ca 100644
--- a/chrome/browser/net/sqlite_persistent_cookie_store.h
+++ b/chrome/browser/net/sqlite_persistent_cookie_store.h
@@ -16,9 +16,12 @@
 #include "net/cookies/cookie_monster.h"
 
 class ClearOnExitPolicy;
-class FilePath;
 class Task;
 
+namespace base {
+class FilePath;
+}
+
 namespace net {
 class CanonicalCookie;
 }
@@ -34,7 +37,7 @@ class SQLitePersistentCookieStore
   // If non-NULL, SQLitePersistentCookieStore will keep a scoped_refptr to the
   // |clear_on_exit_policy| throughout its lifetime.
   SQLitePersistentCookieStore(
-      const FilePath& path,
+      const base::FilePath& path,
       bool restore_old_session_cookies,
       ClearOnExitPolicy* clear_on_exit_policy);
 
diff --git a/chrome/browser/net/sqlite_server_bound_cert_store.h b/chrome/browser/net/sqlite_server_bound_cert_store.h
index 183923a5f3e41b..e20383faec6fd3 100644
--- a/chrome/browser/net/sqlite_server_bound_cert_store.h
+++ b/chrome/browser/net/sqlite_server_bound_cert_store.h
@@ -11,7 +11,10 @@
 #include "net/base/default_server_bound_cert_store.h"
 
 class ClearOnExitPolicy;
+
+namespace base {
 class FilePath;
+}
 
 // Implements the net::DefaultServerBoundCertStore::PersistentStore interface
 // in terms of a SQLite database. For documentation about the actual member
@@ -24,7 +27,7 @@ class SQLiteServerBoundCertStore
  public:
   // If non-NULL, SQLiteServerBoundCertStore will keep a scoped_refptr to the
   // |clear_on_exit_policy| throughout its lifetime.
-  SQLiteServerBoundCertStore(const FilePath& path,
+  SQLiteServerBoundCertStore(const base::FilePath& path,
                              ClearOnExitPolicy* clear_on_exit_policy);
 
   // net::DefaultServerBoundCertStore::PersistentStore:
diff --git a/chrome/browser/net/url_fixer_upper.h b/chrome/browser/net/url_fixer_upper.h
index 72e07a935bc914..0a137d88df1500 100644
--- a/chrome/browser/net/url_fixer_upper.h
+++ b/chrome/browser/net/url_fixer_upper.h
@@ -10,12 +10,14 @@
 #include "base/string16.h"
 #include "googleurl/src/gurl.h"
 
-namespace url_parse {
-  struct Component;
-  struct Parsed;
+namespace base {
+class FilePath;
 }
 
-class FilePath;
+namespace url_parse {
+struct Component;
+struct Parsed;
+}
 
 // This object is designed to convert various types of input into URLs that we
 // know are valid. For example, user typing in the URL bar or command line
@@ -62,7 +64,7 @@ namespace URLFixerUpper {
   // For "regular" input, even if it is possibly a file with a full path, you
   // should use FixupURL() directly.  This function should only be used when
   // relative path handling is desired, as for command line processing.
-  GURL FixupRelativeFile(const FilePath& base_dir, const FilePath& text);
+  GURL FixupRelativeFile(const base::FilePath& base_dir, const base::FilePath& text);
 
   // Offsets the beginning index of |part| by |offset|, which is allowed to be
   // negative.  In some cases, the desired component does not exist at the given
diff --git a/chrome/browser/parsers/metadata_parser.h b/chrome/browser/parsers/metadata_parser.h
index 6700d14b8bba1c..8034a36dbe7d1d 100644
--- a/chrome/browser/parsers/metadata_parser.h
+++ b/chrome/browser/parsers/metadata_parser.h
@@ -7,7 +7,9 @@
 
 #include <string>
 
+namespace base {
 class FilePath;
+}
 
 // Allows for Iteration on the Properties of a given file.
 class MetadataPropertyIterator {
@@ -30,7 +32,7 @@ class MetadataPropertyIterator {
 // Represents a single instance of parsing on a particular file.
 class MetadataParser {
  public:
-  explicit MetadataParser(const FilePath& path) {}
+  explicit MetadataParser(const base::FilePath& path) {}
   virtual ~MetadataParser() {}
 
 
diff --git a/chrome/browser/parsers/metadata_parser_factory.h b/chrome/browser/parsers/metadata_parser_factory.h
index d1d12797fc4719..c6c5a2616f8ed5 100644
--- a/chrome/browser/parsers/metadata_parser_factory.h
+++ b/chrome/browser/parsers/metadata_parser_factory.h
@@ -7,7 +7,9 @@
 
 #include "chrome/browser/parsers/metadata_parser.h"
 
+namespace base {
 class FilePath;
+}
 
 // Used to check to see if a parser can parse a particular file, and allows
 // for creation of a parser on a particular file.
@@ -18,13 +20,13 @@ class MetadataParserFactory {
 
   // Used to check to see if the parser can parse the given file. This
   // should not do any additional reading of the file.
-  virtual bool CanParse(const FilePath& path,
+  virtual bool CanParse(const base::FilePath& path,
                         char* bytes,
                         int bytes_size) = 0;
 
   // Creates the parser on the given file.  Creating the parser does not
   // do any parsing on the file.  Parse has to be called on the parser.
-  virtual MetadataParser* CreateParser(const FilePath& path) = 0;
+  virtual MetadataParser* CreateParser(const base::FilePath& path) = 0;
 };
 
 #endif  // CHROME_BROWSER_PARSERS_METADATA_PARSER_FACTORY_H_
diff --git a/chrome/browser/parsers/metadata_parser_jpeg_factory.h b/chrome/browser/parsers/metadata_parser_jpeg_factory.h
index 705f964d526c1d..1c21144d7ca756 100644
--- a/chrome/browser/parsers/metadata_parser_jpeg_factory.h
+++ b/chrome/browser/parsers/metadata_parser_jpeg_factory.h
@@ -9,17 +9,19 @@
 #include "base/compiler_specific.h"
 #include "chrome/browser/parsers/metadata_parser_factory.h"
 
+namespace base {
 class FilePath;
+}
 
 class MetadataParserJpegFactory : public MetadataParserFactory {
  public:
   MetadataParserJpegFactory();
 
   // Implementation of MetadataParserFactory
-  virtual bool CanParse(const FilePath& path,
+  virtual bool CanParse(const base::FilePath& path,
                         char* bytes,
                         int bytes_size) OVERRIDE;
-  virtual MetadataParser* CreateParser(const FilePath& path) OVERRIDE;
+  virtual MetadataParser* CreateParser(const base::FilePath& path) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MetadataParserJpegFactory);
diff --git a/chrome/browser/parsers/metadata_parser_manager.h b/chrome/browser/parsers/metadata_parser_manager.h
index 910629f25b373e..2d5a759806442b 100644
--- a/chrome/browser/parsers/metadata_parser_manager.h
+++ b/chrome/browser/parsers/metadata_parser_manager.h
@@ -9,9 +9,12 @@
 #include "base/memory/scoped_vector.h"
 
 class MetadataParserFactory;
-class FilePath;
 class MetadataParser;
 
+namespace base {
+class FilePath;
+}
+
 // Metadata Parser manager is used to find the correct parser for a
 // given file.  Allows parsers to register themselves.
 class MetadataParserManager {
@@ -28,7 +31,7 @@ class MetadataParserManager {
   bool RegisterParserFactory(MetadataParserFactory* parser);
 
   // Returns a new metadata parser for a given file.
-  MetadataParser* GetParserForFile(const FilePath& path);
+  MetadataParser* GetParserForFile(const base::FilePath& path);
 
  private:
   ScopedVector<MetadataParserFactory> factories_;
diff --git a/chrome/browser/platform_util.h b/chrome/browser/platform_util.h
index 44fde5da77fa51..629d7566ce3966 100644
--- a/chrome/browser/platform_util.h
+++ b/chrome/browser/platform_util.h
@@ -10,18 +10,21 @@
 #include "base/string16.h"
 #include "ui/gfx/native_widget_types.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace platform_util {
 
 // Show the given file in a file manager. If possible, select the file.
 // Must be called from the UI thread.
-void ShowItemInFolder(const FilePath& full_path);
+void ShowItemInFolder(const base::FilePath& full_path);
 
 // Open the given file in the desktop's default manner.
 // Must be called from the UI thread.
-void OpenItem(const FilePath& full_path);
+void OpenItem(const base::FilePath& full_path);
 
 // Open the given external protocol URL in the desktop's default manner.
 // (For example, mailto: URLs in the default mail user agent.)
diff --git a/chrome/browser/platform_util_android.cc b/chrome/browser/platform_util_android.cc
index b938f5db84ace9..e29bea88dda971 100644
--- a/chrome/browser/platform_util_android.cc
+++ b/chrome/browser/platform_util_android.cc
@@ -10,11 +10,11 @@ namespace platform_util {
 
 // TODO: crbug/115682 to track implementation of the following methods.
 
-void ShowItemInFolder(const FilePath& full_path) {
+void ShowItemInFolder(const base::FilePath& full_path) {
   NOTIMPLEMENTED();
 }
 
-void OpenItem(const FilePath& full_path) {
+void OpenItem(const base::FilePath& full_path) {
   NOTIMPLEMENTED();
 }
 
diff --git a/chrome/browser/plugins/plugin_installer.h b/chrome/browser/plugins/plugin_installer.h
index ac872ddd174cd6..36b7eb3cb8b640 100644
--- a/chrome/browser/plugins/plugin_installer.h
+++ b/chrome/browser/plugins/plugin_installer.h
@@ -13,7 +13,6 @@
 #include "googleurl/src/gurl.h"
 #include "net/base/net_errors.h"
 
-class FilePath;
 class PluginInstallerObserver;
 class WeakPluginInstallerObserver;
 
diff --git a/chrome/browser/prefs/chrome_pref_service_factory.h b/chrome/browser/prefs/chrome_pref_service_factory.h
index 84e5a637400ef7..7ba5053f44fcfb 100644
--- a/chrome/browser/prefs/chrome_pref_service_factory.h
+++ b/chrome/browser/prefs/chrome_pref_service_factory.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_PREFS_CHROME_PREF_SERVICE_FACTORY_H_
 
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }
 
@@ -13,7 +14,6 @@ namespace policy {
 class PolicyService;
 }
 
-class FilePath;
 class PrefServiceSimple;
 class PrefServiceSyncable;
 class PrefStore;
@@ -35,14 +35,14 @@ namespace chrome_prefs {
 // function returned.
 
 PrefServiceSimple* CreateLocalState(
-    const FilePath& pref_filename,
+    const base::FilePath& pref_filename,
     base::SequencedTaskRunner* pref_io_task_runner,
     policy::PolicyService* policy_service,
     PrefStore* extension_prefs,
     bool async);
 
 PrefServiceSyncable* CreateProfilePrefs(
-    const FilePath& pref_filename,
+    const base::FilePath& pref_filename,
     base::SequencedTaskRunner* pref_io_task_runner,
     policy::PolicyService* policy_service,
     PrefStore* extension_prefs,
diff --git a/chrome/browser/prefs/pref_service.h b/chrome/browser/prefs/pref_service.h
index ff57a72d6bccf9..0bc7f77aa8e83a 100644
--- a/chrome/browser/prefs/pref_service.h
+++ b/chrome/browser/prefs/pref_service.h
@@ -119,7 +119,7 @@ class PrefService : public PrefServiceBase, public base::NonThreadSafe {
   virtual int GetInteger(const char* path) const OVERRIDE;
   virtual double GetDouble(const char* path) const OVERRIDE;
   virtual std::string GetString(const char* path) const OVERRIDE;
-  virtual FilePath GetFilePath(const char* path) const OVERRIDE;
+  virtual base::FilePath GetFilePath(const char* path) const OVERRIDE;
   virtual const base::DictionaryValue* GetDictionary(
       const char* path) const OVERRIDE;
   virtual const base::ListValue* GetList(const char* path) const OVERRIDE;
@@ -129,7 +129,8 @@ class PrefService : public PrefServiceBase, public base::NonThreadSafe {
   virtual void SetInteger(const char* path, int value) OVERRIDE;
   virtual void SetDouble(const char* path, double value) OVERRIDE;
   virtual void SetString(const char* path, const std::string& value) OVERRIDE;
-  virtual void SetFilePath(const char* path, const FilePath& value) OVERRIDE;
+  virtual void SetFilePath(const char* path,
+                           const base::FilePath& value) OVERRIDE;
   virtual void SetInt64(const char* path, int64 value) OVERRIDE;
   virtual int64 GetInt64(const char* path) const OVERRIDE;
   virtual void SetUint64(const char* path, uint64 value) OVERRIDE;
diff --git a/chrome/browser/prefs/pref_service_builder.h b/chrome/browser/prefs/pref_service_builder.h
index adcbdf06070b36..208e334feff024 100644
--- a/chrome/browser/prefs/pref_service_builder.h
+++ b/chrome/browser/prefs/pref_service_builder.h
@@ -11,10 +11,10 @@
 #include "base/prefs/persistent_pref_store.h"
 #include "base/prefs/pref_store.h"
 
-class FilePath;
 class PrefServiceSimple;
 
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }
 
@@ -40,7 +40,7 @@ class PrefServiceBuilder {
 
   // Specifies to use an actual file-backed user pref store.
   PrefServiceBuilder& WithUserFilePrefs(
-      const FilePath& prefs_file,
+      const base::FilePath& prefs_file,
       base::SequencedTaskRunner* task_runner);
 
   PrefServiceBuilder& WithAsync(bool async);
diff --git a/chrome/browser/prefs/pref_service_simple.h b/chrome/browser/prefs/pref_service_simple.h
index c37d7d048d520a..fd1e612383cac0 100644
--- a/chrome/browser/prefs/pref_service_simple.h
+++ b/chrome/browser/prefs/pref_service_simple.h
@@ -26,7 +26,8 @@ class PrefServiceSimple : public PrefService {
   void RegisterIntegerPref(const char* path, int default_value);
   void RegisterDoublePref(const char* path, double default_value);
   void RegisterStringPref(const char* path, const std::string& default_value);
-  void RegisterFilePathPref(const char* path, const FilePath& default_value);
+  void RegisterFilePathPref(const char* path,
+                            const base::FilePath& default_value);
   void RegisterListPref(const char* path);
   void RegisterDictionaryPref(const char* path);
   void RegisterListPref(const char* path, base::ListValue* default_value);
diff --git a/chrome/browser/prefs/pref_service_syncable.h b/chrome/browser/prefs/pref_service_syncable.h
index c0da1356977e11..f280d7ca68b19c 100644
--- a/chrome/browser/prefs/pref_service_syncable.h
+++ b/chrome/browser/prefs/pref_service_syncable.h
@@ -70,7 +70,7 @@ class PrefServiceSyncable : public PrefService {
                           const std::string& default_value,
                           PrefSyncStatus sync_status);
   void RegisterFilePathPref(const char* path,
-                            const FilePath& default_value,
+                            const base::FilePath& default_value,
                             PrefSyncStatus sync_status);
   void RegisterListPref(const char* path,
                         PrefSyncStatus sync_status);
diff --git a/chrome/browser/printing/print_dialog_cloud.h b/chrome/browser/printing/print_dialog_cloud.h
index 98cf1b57c4fedd..752664627a4a11 100644
--- a/chrome/browser/printing/print_dialog_cloud.h
+++ b/chrome/browser/printing/print_dialog_cloud.h
@@ -13,9 +13,12 @@
 #include "base/string16.h"
 #include "ui/gfx/native_widget_types.h"
 
-class FilePath;
 class CommandLine;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class BrowserContext;
 }
@@ -29,7 +32,7 @@ namespace print_dialog_cloud {
 // to.
 void CreatePrintDialogForFile(content::BrowserContext* browser_context,
                               gfx::NativeWindow modal_parent,
-                              const FilePath& path_to_file,
+                              const base::FilePath& path_to_file,
                               const string16& print_job_title,
                               const string16& print_ticket,
                               const std::string& file_type,
diff --git a/chrome/browser/printing/printing_message_filter.h b/chrome/browser/printing/printing_message_filter.h
index d8fdc92faf49d7..5347526674e598 100644
--- a/chrome/browser/printing/printing_message_filter.h
+++ b/chrome/browser/printing/printing_message_filter.h
@@ -14,13 +14,13 @@
 #include "base/shared_memory.h"
 #endif
 
-class FilePath;
 struct PrintHostMsg_ScriptedPrint_Params;
 class Profile;
 class ProfileIOData;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace content {
@@ -60,7 +60,7 @@ class PrintingMessageFilter : public content::BrowserMessageFilter {
   void OnAllocateTempFileForPrinting(base::FileDescriptor* temp_file_fd,
                                      int* sequence_number);
   void OnTempFileForPrintingWritten(int render_view_id, int sequence_number);
-  void CreatePrintDialogForFile(int render_view_id, const FilePath& path);
+  void CreatePrintDialogForFile(int render_view_id, const base::FilePath& path);
 #endif
 
   // Given a render_view_id get the corresponding WebContents.
diff --git a/chrome/browser/profiles/profile.h b/chrome/browser/profiles/profile.h
index 02d1b090cdef57..40ca85de73bb64 100644
--- a/chrome/browser/profiles/profile.h
+++ b/chrome/browser/profiles/profile.h
@@ -143,7 +143,7 @@ class Profile : public content::BrowserContext {
 
   // Create a new profile given a path. If |create_mode| is
   // CREATE_MODE_ASYNCHRONOUS then the profile is initialized asynchronously.
-  static Profile* CreateProfile(const FilePath& path,
+  static Profile* CreateProfile(const base::FilePath& path,
                                 Delegate* delegate,
                                 CreateMode create_mode);
 
@@ -227,7 +227,7 @@ class Profile : public content::BrowserContext {
 
   // Returns the request context used within |partition_id|.
   virtual net::URLRequestContextGetter* GetRequestContextForStoragePartition(
-      const FilePath& partition_path,
+      const base::FilePath& partition_path,
       bool in_memory) = 0;
 
   // Returns the SSLConfigService for this profile.
@@ -253,8 +253,8 @@ class Profile : public content::BrowserContext {
   virtual base::Time GetStartTime() const = 0;
 
   // Returns the last directory that was chosen for uploading or opening a file.
-  virtual FilePath last_selected_directory() = 0;
-  virtual void set_last_selected_directory(const FilePath& path) = 0;
+  virtual base::FilePath last_selected_directory() = 0;
+  virtual void set_last_selected_directory(const base::FilePath& path) = 0;
 
 #if defined(OS_CHROMEOS)
   enum AppLocaleChangedVia {
diff --git a/chrome/browser/profiles/profile_info_cache_observer.h b/chrome/browser/profiles/profile_info_cache_observer.h
index 853f8ddae10b1e..746c1ed833f89f 100644
--- a/chrome/browser/profiles/profile_info_cache_observer.h
+++ b/chrome/browser/profiles/profile_info_cache_observer.h
@@ -8,7 +8,9 @@
 #include "base/string16.h"
 #include "ui/gfx/image/image.h"
 
+namespace base {
 class FilePath;
+}
 
 // This class provides an Observer interface to watch for changes to the
 // ProfileInfoCache.
@@ -16,13 +18,13 @@ class ProfileInfoCacheObserver {
  public:
   virtual ~ProfileInfoCacheObserver() {}
 
-  virtual void OnProfileAdded(const FilePath& profile_path) = 0;
-  virtual void OnProfileWillBeRemoved(const FilePath& profile_path) = 0;
-  virtual void OnProfileWasRemoved(const FilePath& profile_path,
+  virtual void OnProfileAdded(const base::FilePath& profile_path) = 0;
+  virtual void OnProfileWillBeRemoved(const base::FilePath& profile_path) = 0;
+  virtual void OnProfileWasRemoved(const base::FilePath& profile_path,
                                    const string16& profile_name) = 0;
-  virtual void OnProfileNameChanged(const FilePath& profile_path,
+  virtual void OnProfileNameChanged(const base::FilePath& profile_path,
                                     const string16& old_profile_name) = 0;
-  virtual void OnProfileAvatarChanged(const FilePath& profile_path) = 0;
+  virtual void OnProfileAvatarChanged(const base::FilePath& profile_path) = 0;
 
  protected:
   ProfileInfoCacheObserver() {}
diff --git a/chrome/browser/profiles/profile_info_cache_unittest.h b/chrome/browser/profiles/profile_info_cache_unittest.h
index 640f4da60ef7f7..ec2ec70be40f8e 100644
--- a/chrome/browser/profiles/profile_info_cache_unittest.h
+++ b/chrome/browser/profiles/profile_info_cache_unittest.h
@@ -13,9 +13,12 @@
 #include "content/public/test/test_browser_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-class FilePath;
 class ProfileInfoCache;
 
+namespace base {
+class FilePath;
+}
+
 // Class used to test that ProfileInfoCache does not try to access any
 // unexpected profile names.
 class ProfileNameVerifierObserver : public ProfileInfoCacheObserver {
@@ -25,16 +28,16 @@ class ProfileNameVerifierObserver : public ProfileInfoCacheObserver {
   virtual ~ProfileNameVerifierObserver();
 
   // ProfileInfoCacheObserver overrides:
-  virtual void OnProfileAdded(const FilePath& profile_path) OVERRIDE;
+  virtual void OnProfileAdded(const base::FilePath& profile_path) OVERRIDE;
   virtual void OnProfileWillBeRemoved(
-      const FilePath& profile_path) OVERRIDE;
+      const base::FilePath& profile_path) OVERRIDE;
   virtual void OnProfileWasRemoved(
-      const FilePath& profile_path,
+      const base::FilePath& profile_path,
       const string16& profile_name) OVERRIDE;
   virtual void OnProfileNameChanged(
-      const FilePath& profile_path,
+      const base::FilePath& profile_path,
       const string16& old_profile_name) OVERRIDE;
-  virtual void OnProfileAvatarChanged(const FilePath& profile_path) OVERRIDE;
+  virtual void OnProfileAvatarChanged(const base::FilePath& profile_path) OVERRIDE;
 
  private:
   ProfileInfoCache* GetCache();
@@ -52,7 +55,7 @@ class ProfileInfoCacheTest : public testing::Test {
   virtual void TearDown() OVERRIDE;
 
   ProfileInfoCache* GetCache();
-  FilePath GetProfilePath(const std::string& base_name);
+  base::FilePath GetProfilePath(const std::string& base_name);
   void ResetCache();
 
  protected:
diff --git a/chrome/browser/profiles/profile_metrics.h b/chrome/browser/profiles/profile_metrics.h
index 2850a4fae77d56..c74a8ced884c54 100644
--- a/chrome/browser/profiles/profile_metrics.h
+++ b/chrome/browser/profiles/profile_metrics.h
@@ -10,9 +10,12 @@
 
 #include "base/basictypes.h"
 
-class FilePath;
 class ProfileManager;
 
+namespace base {
+class FilePath;
+}
+
 class ProfileMetrics {
  public:
   // Enum for counting the ways users were added.
@@ -80,9 +83,9 @@ class ProfileMetrics {
 
   // These functions should only be called on the UI thread because they hook
   // into g_browser_process through a helper function.
-  static void LogProfileLaunch(const FilePath& profile_path);
-  static void LogProfileSyncSignIn(const FilePath& profile_path);
-  static void LogProfileUpdate(const FilePath& profile_path);
+  static void LogProfileLaunch(const base::FilePath& profile_path);
+  static void LogProfileSyncSignIn(const base::FilePath& profile_path);
+  static void LogProfileUpdate(const base::FilePath& profile_path);
 };
 
 
diff --git a/chrome/browser/renderer_host/pepper/pepper_flash_device_id_host.h b/chrome/browser/renderer_host/pepper/pepper_flash_device_id_host.h
index 3980f366fae873..f3cf5680eb627d 100644
--- a/chrome/browser/renderer_host/pepper/pepper_flash_device_id_host.h
+++ b/chrome/browser/renderer_host/pepper/pepper_flash_device_id_host.h
@@ -11,7 +11,9 @@
 #include "ppapi/host/resource_host.h"
 #include "ppapi/proxy/resource_message_params.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 class BrowserPpapiHost;
@@ -63,7 +65,7 @@ class PepperFlashDeviceIDHost : public ppapi::host::ResourceHost {
     // Called on the file thread to read the contents of the file and to
     // forward it to the IO thread. The path will be empty on error (in
     // which case it will forward the empty string to the IO thread).
-    void ReadDRMFileOnFileThread(const FilePath& path);
+    void ReadDRMFileOnFileThread(const base::FilePath& path);
 
     // Called on the IO thread to call back into the device ID host with the
     // file contents, or the empty string on failure.
diff --git a/chrome/browser/safe_browsing/prefix_set.h b/chrome/browser/safe_browsing/prefix_set.h
index 914dd5edb83734..064c19252900f0 100644
--- a/chrome/browser/safe_browsing/prefix_set.h
+++ b/chrome/browser/safe_browsing/prefix_set.h
@@ -53,7 +53,9 @@
 
 #include "chrome/browser/safe_browsing/safe_browsing_util.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace safe_browsing {
 
@@ -66,8 +68,8 @@ class PrefixSet {
   bool Exists(SBPrefix prefix) const;
 
   // Persist the set on disk.
-  static PrefixSet* LoadFile(const FilePath& filter_name);
-  bool WriteFile(const FilePath& filter_name) const;
+  static PrefixSet* LoadFile(const base::FilePath& filter_name);
+  bool WriteFile(const base::FilePath& filter_name) const;
 
   // Regenerate the vector of prefixes passed to the constructor into
   // |prefixes|.  Prefixes will be added in sorted order.
diff --git a/chrome/browser/safe_browsing/safe_browsing_store.h b/chrome/browser/safe_browsing/safe_browsing_store.h
index 731f3193a92869..d88fedb69fd823 100644
--- a/chrome/browser/safe_browsing/safe_browsing_store.h
+++ b/chrome/browser/safe_browsing/safe_browsing_store.h
@@ -14,7 +14,9 @@
 #include "base/time.h"
 #include "chrome/browser/safe_browsing/safe_browsing_util.h"
 
+namespace base {
 class FilePath;
+}
 
 // SafeBrowsingStore provides a storage abstraction for the
 // safe-browsing data used to build the bloom filter.  The items
@@ -163,7 +165,7 @@ class SafeBrowsingStore {
   // is detected, which could happen as part of any call other than
   // Delete().  The appropriate action is to use Delete() to clear the
   // store.
-  virtual void Init(const FilePath& filename,
+  virtual void Init(const base::FilePath& filename,
                     const base::Closure& corruption_callback) = 0;
 
   // Deletes the files which back the store, returning true if
diff --git a/chrome/browser/safe_browsing/safe_browsing_store_unittest_helper.h b/chrome/browser/safe_browsing/safe_browsing_store_unittest_helper.h
index 20a0fc326d2a9c..5854523072f694 100644
--- a/chrome/browser/safe_browsing/safe_browsing_store_unittest_helper.h
+++ b/chrome/browser/safe_browsing/safe_browsing_store_unittest_helper.h
@@ -41,7 +41,7 @@ void SafeBrowsingStoreTestDeleteChunks(SafeBrowsingStore* store);
 
 // Test that deleting the store deletes the store.
 void SafeBrowsingStoreTestDelete(SafeBrowsingStore* store,
-                                 const FilePath& filename);
+                                 const base::FilePath& filename);
 
 // Wrap all the tests up for implementation subclasses.
 // |test_fixture| is the class that would be passed to TEST_F(),
diff --git a/chrome/browser/safe_browsing/signature_util.h b/chrome/browser/safe_browsing/signature_util.h
index 2233a55cb806ee..00aef61e088a30 100644
--- a/chrome/browser/safe_browsing/signature_util.h
+++ b/chrome/browser/safe_browsing/signature_util.h
@@ -11,7 +11,9 @@
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace safe_browsing {
 class ClientDownloadRequest_SignatureInfo;
@@ -23,7 +25,7 @@ class SignatureUtil : public base::RefCountedThreadSafe<SignatureUtil> {
   // Fills in the DownloadRequest_SignatureInfo for the given file path.
   // This method may be called on any thread.
   virtual void CheckSignature(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       ClientDownloadRequest_SignatureInfo* signature_info);
 
  protected:
diff --git a/chrome/browser/safe_browsing/signature_util_posix.cc b/chrome/browser/safe_browsing/signature_util_posix.cc
index b3c2b1752da6c2..7a98a5485dfd1d 100644
--- a/chrome/browser/safe_browsing/signature_util_posix.cc
+++ b/chrome/browser/safe_browsing/signature_util_posix.cc
@@ -14,7 +14,7 @@ SignatureUtil::SignatureUtil() {}
 SignatureUtil::~SignatureUtil() {}
 
 void SignatureUtil::CheckSignature(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     ClientDownloadRequest_SignatureInfo* signature_info) {}
 
 }  // namespace safe_browsing
diff --git a/chrome/browser/sync_file_system/mock_remote_change_processor.h b/chrome/browser/sync_file_system/mock_remote_change_processor.h
index ebf196909032e5..a48cd36c7cc037 100644
--- a/chrome/browser/sync_file_system/mock_remote_change_processor.h
+++ b/chrome/browser/sync_file_system/mock_remote_change_processor.h
@@ -11,7 +11,9 @@
 #include "webkit/fileapi/syncable/file_change.h"
 #include "webkit/fileapi/syncable/sync_callbacks.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace fileapi {
 class FileSystemURL;
@@ -31,7 +33,7 @@ class MockRemoteChangeProcessor : public RemoteChangeProcessor {
                     const PrepareChangeCallback& callback));
   MOCK_METHOD4(ApplyRemoteChange,
                void(const fileapi::FileChange& change,
-                    const FilePath& local_path,
+                    const base::FilePath& local_path,
                     const fileapi::FileSystemURL& url,
                     const fileapi::SyncStatusCallback& callback));
   MOCK_METHOD2(ClearLocalChanges,
diff --git a/chrome/browser/sync_file_system/remote_change_processor.h b/chrome/browser/sync_file_system/remote_change_processor.h
index e76a8262f00308..8fb00ad448a17d 100644
--- a/chrome/browser/sync_file_system/remote_change_processor.h
+++ b/chrome/browser/sync_file_system/remote_change_processor.h
@@ -10,7 +10,9 @@
 #include "webkit/fileapi/syncable/sync_callbacks.h"
 #include "webkit/fileapi/syncable/sync_status_code.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace fileapi {
 class FileChange;
@@ -59,7 +61,7 @@ class RemoteChangeProcessor {
   // have disabled any further writing).
   virtual void ApplyRemoteChange(
       const fileapi::FileChange& change,
-      const FilePath& local_path,
+      const base::FilePath& local_path,
       const fileapi::FileSystemURL& url,
       const fileapi::SyncStatusCallback& callback) = 0;
 
diff --git a/chrome/browser/system_monitor/media_transfer_protocol_device_observer_linux.h b/chrome/browser/system_monitor/media_transfer_protocol_device_observer_linux.h
index fd40f1f01aae7f..45c9e67ae66c83 100644
--- a/chrome/browser/system_monitor/media_transfer_protocol_device_observer_linux.h
+++ b/chrome/browser/system_monitor/media_transfer_protocol_device_observer_linux.h
@@ -12,7 +12,9 @@
 #include "chrome/browser/system_monitor/removable_storage_notifications.h"
 #include "device/media_transfer_protocol/media_transfer_protocol_manager.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
@@ -37,7 +39,7 @@ class MediaTransferProtocolDeviceObserverLinux
   // Finds the storage that contains |path| and populates |storage_info|.
   // Returns false if unable to find the storage.
   bool GetStorageInfoForPath(
-      const FilePath& path,
+      const base::FilePath& path,
       RemovableStorageNotifications::StorageInfo* storage_info) const;
 
  protected:
diff --git a/chrome/browser/system_monitor/portable_device_watcher_win.h b/chrome/browser/system_monitor/portable_device_watcher_win.h
index 5f0e9d80038178..0d16ba63bf11b8 100644
--- a/chrome/browser/system_monitor/portable_device_watcher_win.h
+++ b/chrome/browser/system_monitor/portable_device_watcher_win.h
@@ -20,8 +20,6 @@ namespace base {
 class SequencedTaskRunner;
 }
 
-class FilePath;
-
 namespace chrome {
 
 namespace test {
diff --git a/chrome/browser/system_monitor/removable_device_notifications_linux.h b/chrome/browser/system_monitor/removable_device_notifications_linux.h
index cd595c99eab9d3..dea7424907587f 100644
--- a/chrome/browser/system_monitor/removable_device_notifications_linux.h
+++ b/chrome/browser/system_monitor/removable_device_notifications_linux.h
@@ -25,11 +25,13 @@
 #include "chrome/browser/system_monitor/removable_storage_notifications.h"
 #include "content/public/browser/browser_thread.h"
 
+namespace base {
 class FilePath;
+}
 
 // Gets device information given a |device_path|. On success, fills in
 // |unique_id|, |name|, |removable| and |partition_size_in_bytes|.
-typedef void (*GetDeviceInfoFunc)(const FilePath& device_path,
+typedef void (*GetDeviceInfoFunc)(const base::FilePath& device_path,
                                   std::string* unique_id,
                                   string16* name,
                                   bool* removable,
@@ -43,7 +45,7 @@ class RemovableDeviceNotificationsLinux
           content::BrowserThread::DeleteOnFileThread> {
  public:
   // Should only be called by browser start up code.  Use GetInstance() instead.
-  explicit RemovableDeviceNotificationsLinux(const FilePath& path);
+  explicit RemovableDeviceNotificationsLinux(const base::FilePath& path);
 
   // Must be called for RemovableDeviceNotificationsLinux to work.
   void Init();
@@ -51,7 +53,7 @@ class RemovableDeviceNotificationsLinux
   // Finds the device that contains |path| and populates |device_info|.
   // Returns false if unable to find the device.
   virtual bool GetDeviceInfoForPath(
-      const FilePath& path,
+      const base::FilePath& path,
       StorageInfo* device_info) const OVERRIDE;
 
   // Returns the storage partition size of the device present at |location|.
@@ -60,7 +62,7 @@ class RemovableDeviceNotificationsLinux
 
  protected:
   // Only for use in unit tests.
-  RemovableDeviceNotificationsLinux(const FilePath& path,
+  RemovableDeviceNotificationsLinux(const base::FilePath& path,
                                     GetDeviceInfoFunc getDeviceInfo);
 
   // Avoids code deleting the object while there are references to it.
@@ -69,7 +71,7 @@ class RemovableDeviceNotificationsLinux
   // error.
   virtual ~RemovableDeviceNotificationsLinux();
 
-  virtual void OnFilePathChanged(const FilePath& path, bool error);
+  virtual void OnFilePathChanged(const base::FilePath& path, bool error);
 
  private:
   friend class base::RefCountedThreadSafe<RemovableDeviceNotificationsLinux>;
@@ -82,24 +84,24 @@ class RemovableDeviceNotificationsLinux
   struct MountPointInfo {
     MountPointInfo();
 
-    FilePath mount_device;
+    base::FilePath mount_device;
     std::string device_id;
     string16 device_name;
     uint64 partition_size_in_bytes;
   };
 
   // Mapping of mount points to MountPointInfo.
-  typedef std::map<FilePath, MountPointInfo> MountMap;
+  typedef std::map<base::FilePath, MountPointInfo> MountMap;
 
   // (mount point, priority)
   // For devices that are mounted to multiple mount points, this helps us track
   // which one we've notified system monitor about.
-  typedef std::map<FilePath, bool> ReferencedMountPoint;
+  typedef std::map<base::FilePath, bool> ReferencedMountPoint;
 
   // (mount device, map of known mount points)
   // For each mount device, track the places it is mounted and which one (if
   // any) we have notified system monitor about.
-  typedef std::map<FilePath, ReferencedMountPoint> MountPriorityMap;
+  typedef std::map<base::FilePath, ReferencedMountPoint> MountPriorityMap;
 
   // Do initialization on the File Thread.
   void InitOnFileThread();
@@ -109,13 +111,13 @@ class RemovableDeviceNotificationsLinux
 
   // Adds |mount_device| as mounted on |mount_point|.  If the device is a new
   // device any listeners are notified.
-  void AddNewMount(const FilePath& mount_device, const FilePath& mount_point);
+  void AddNewMount(const base::FilePath& mount_device, const base::FilePath& mount_point);
 
   // Whether Init() has been called or not.
   bool initialized_;
 
   // Mtab file that lists the mount points.
-  const FilePath mtab_path_;
+  const base::FilePath mtab_path_;
 
   // Watcher for |mtab_path_|.
   base::FilePathWatcher file_watcher_;
diff --git a/chrome/browser/system_monitor/removable_device_notifications_window_win.h b/chrome/browser/system_monitor/removable_device_notifications_window_win.h
index a2afd31889438e..deb4bc54e58ba9 100644
--- a/chrome/browser/system_monitor/removable_device_notifications_window_win.h
+++ b/chrome/browser/system_monitor/removable_device_notifications_window_win.h
@@ -10,7 +10,9 @@
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/system_monitor/removable_storage_notifications.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
@@ -35,7 +37,7 @@ class RemovableDeviceNotificationsWindowWin
 
   // RemovableStorageNotifications:
   virtual bool GetDeviceInfoForPath(
-      const FilePath& path,
+      const base::FilePath& path,
       StorageInfo* device_info) const OVERRIDE;
   virtual uint64 GetStorageSize(const std::string& location) const OVERRIDE;
   virtual bool GetMTPStorageInfoFromDeviceId(
@@ -57,7 +59,7 @@ class RemovableDeviceNotificationsWindowWin
   // Gets the removable storage information given a |device_path|. On success,
   // returns true and fills in |device_location|, |unique_id|, |name| and
   // |removable|.
-  bool GetDeviceInfo(const FilePath& device_path,
+  bool GetDeviceInfo(const base::FilePath& device_path,
                      string16* device_location,
                      std::string* unique_id,
                      string16* name,
diff --git a/chrome/browser/system_monitor/test_volume_mount_watcher_win.h b/chrome/browser/system_monitor/test_volume_mount_watcher_win.h
index 0771d70ca4167f..a4b722719260a5 100644
--- a/chrome/browser/system_monitor/test_volume_mount_watcher_win.h
+++ b/chrome/browser/system_monitor/test_volume_mount_watcher_win.h
@@ -15,7 +15,9 @@
 #include "base/synchronization/waitable_event.h"
 #include "chrome/browser/system_monitor/volume_mount_watcher_win.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 namespace test {
@@ -25,7 +27,7 @@ class TestVolumeMountWatcherWin : public VolumeMountWatcherWin {
   TestVolumeMountWatcherWin();
   virtual ~TestVolumeMountWatcherWin();
 
-  void AddDeviceForTesting(const FilePath& device_path,
+  void AddDeviceForTesting(const base::FilePath& device_path,
                            const std::string& device_id,
                            const std::string& unique_id,
                            const string16& device_name,
@@ -35,30 +37,30 @@ class TestVolumeMountWatcherWin : public VolumeMountWatcherWin {
 
   void FlushWorkerPoolForTesting();
 
-  virtual void DeviceCheckComplete(const FilePath& device_path);
+  virtual void DeviceCheckComplete(const base::FilePath& device_path);
 
-  std::vector<FilePath> devices_checked() const { return devices_checked_; }
+  std::vector<base::FilePath> devices_checked() const { return devices_checked_; }
 
   void BlockDeviceCheckForTesting();
 
   void ReleaseDeviceCheck();
 
   // VolumeMountWatcherWin:
-  virtual bool GetDeviceInfo(const FilePath& device_path,
+  virtual bool GetDeviceInfo(const base::FilePath& device_path,
                              string16* device_location,
                              std::string* unique_id,
                              string16* name,
                              bool* removable) const OVERRIDE;
-  virtual std::vector<FilePath> GetAttachedDevices();
+  virtual std::vector<base::FilePath> GetAttachedDevices();
 
-  bool GetRawDeviceInfo(const FilePath& device_path,
+  bool GetRawDeviceInfo(const base::FilePath& device_path,
                         string16* device_location,
                         std::string* unique_id,
                         string16* name,
                         bool* removable);
 
  private:
-  std::vector<FilePath> devices_checked_;
+  std::vector<base::FilePath> devices_checked_;
   scoped_ptr<base::WaitableEvent> device_check_complete_event_;
 
   DISALLOW_COPY_AND_ASSIGN(TestVolumeMountWatcherWin);
diff --git a/chrome/browser/system_monitor/udev_util_linux.h b/chrome/browser/system_monitor/udev_util_linux.h
index c138f4c9c011f4..dffcb9fa22c470 100644
--- a/chrome/browser/system_monitor/udev_util_linux.h
+++ b/chrome/browser/system_monitor/udev_util_linux.h
@@ -11,7 +11,9 @@
 
 #include "base/memory/scoped_generic_obj.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
@@ -42,7 +44,7 @@ std::string GetUdevDevicePropertyValue(struct udev_device* udev_device,
 
 // Helper for udev_device_new_from_syspath()/udev_device_get_property_value()
 // pair. |device_path| is the absolute path to the device, including /sys.
-bool GetUdevDevicePropertyValueByPath(const FilePath& device_path,
+bool GetUdevDevicePropertyValueByPath(const base::FilePath& device_path,
                                       const char* key,
                                       std::string* result);
 
diff --git a/chrome/browser/task_profiler/task_profiler_data_serializer.h b/chrome/browser/task_profiler/task_profiler_data_serializer.h
index 6c2020e002a118..9d58f3cc150aa4 100644
--- a/chrome/browser/task_profiler/task_profiler_data_serializer.h
+++ b/chrome/browser/task_profiler/task_profiler_data_serializer.h
@@ -8,10 +8,9 @@
 #include "base/basictypes.h"
 #include "content/public/common/process_type.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace tracked_objects {
@@ -31,7 +30,7 @@ class TaskProfilerDataSerializer {
                       content::ProcessType process_type,
                       base::DictionaryValue* dictionary);
 
-  bool WriteToFile(const FilePath& path);
+  bool WriteToFile(const base::FilePath& path);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TaskProfilerDataSerializer);
diff --git a/chrome/browser/themes/browser_theme_pack.h b/chrome/browser/themes/browser_theme_pack.h
index d15aeb592441e8..64475666640b04 100644
--- a/chrome/browser/themes/browser_theme_pack.h
+++ b/chrome/browser/themes/browser_theme_pack.h
@@ -18,10 +18,9 @@
 #include "ui/base/layout.h"
 #include "ui/gfx/color_utils.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 class RefCountedMemory;
 }
 
@@ -67,14 +66,14 @@ class BrowserThemePack : public base::RefCountedThreadSafe<
   // operation should be relatively fast, as it should be an mmap() and some
   // pointer swizzling. Returns NULL on any error attempting to read |path|.
   static scoped_refptr<BrowserThemePack> BuildFromDataPack(
-      const FilePath& path, const std::string& expected_id);
+      const base::FilePath& path, const std::string& expected_id);
 
   // Builds a data pack on disk at |path| for future quick loading by
   // BuildFromDataPack(). Often (but not always) called from the file thread;
   // implementation should be threadsafe because neither thread will write to
   // |image_memory_| and the worker thread will keep a reference to prevent
   // destruction.
-  bool WriteToDisk(const FilePath& path) const;
+  bool WriteToDisk(const base::FilePath& path) const;
 
   // If this theme specifies data for the corresponding |id|, return true and
   // write the corresponding value to the output parameter. These functions
@@ -112,8 +111,8 @@ class BrowserThemePack : public base::RefCountedThreadSafe<
   // The type passed to ui::DataPack::WritePack.
   typedef std::map<uint16, base::StringPiece> RawDataForWriting;
 
-  // An association between an id and the FilePath that has the image data.
-  typedef std::map<int, FilePath> FilePathMap;
+  // An association between an id and the base::FilePath that has the image data.
+  typedef std::map<int, base::FilePath> FilePathMap;
 
   // Default. Everything is empty.
   BrowserThemePack();
@@ -141,7 +140,7 @@ class BrowserThemePack : public base::RefCountedThreadSafe<
 
   // Parses the image names out of an extension.
   void ParseImageNamesFromJSON(base::DictionaryValue* images_value,
-                               const FilePath& images_path,
+                               const base::FilePath& images_path,
                                FilePathMap* file_paths) const;
 
   // Creates the data for |source_images_| from |file_paths|.
diff --git a/chrome/browser/themes/theme_service.h b/chrome/browser/themes/theme_service.h
index 89942ed3a20577..29b9778e960d7d 100644
--- a/chrome/browser/themes/theme_service.h
+++ b/chrome/browser/themes/theme_service.h
@@ -20,9 +20,12 @@
 class BrowserThemePack;
 class ThemeServiceTest;
 class ThemeSyncableService;
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 namespace color_utils {
 struct HSL;
 }
@@ -247,7 +250,7 @@ class ThemeService : public base::NonThreadSafe,
   virtual ThemeSyncableService* GetThemeSyncableService() const;
 
   // Save the images to be written to disk, mapping file path to id.
-  typedef std::map<FilePath, int> ImagesDiskCache;
+  typedef std::map<base::FilePath, int> ImagesDiskCache;
 
  protected:
   // Get the specified tint - |id| is one of the TINT_* enum values.
@@ -277,7 +280,7 @@ class ThemeService : public base::NonThreadSafe,
   friend class ThemeServiceTest;
 
   // Saves the filename of the cached theme pack.
-  void SavePackName(const FilePath& pack_path);
+  void SavePackName(const base::FilePath& pack_path);
 
   // Save the id of the last theme installed.
   void SaveThemeID(const std::string& id);
diff --git a/chrome/browser/ui/browser_command_controller.h b/chrome/browser/ui/browser_command_controller.h
index 8d4eefe7300cb0..f65780bdf46a36 100644
--- a/chrome/browser/ui/browser_command_controller.h
+++ b/chrome/browser/ui/browser_command_controller.h
@@ -102,13 +102,14 @@ class BrowserCommandController : public CommandUpdaterDelegate,
                        const content::NotificationDetails& details) OVERRIDE;
 
   // Overridden from ProfileInfoCacheObserver:
-  virtual void OnProfileAdded(const FilePath& profile_path) OVERRIDE;
-  virtual void OnProfileWillBeRemoved(const FilePath& profile_path) OVERRIDE;
-  virtual void OnProfileWasRemoved(const FilePath& profile_path,
+  virtual void OnProfileAdded(const base::FilePath& profile_path) OVERRIDE;
+  virtual void OnProfileWillBeRemoved(
+      const base::FilePath& profile_path) OVERRIDE;
+  virtual void OnProfileWasRemoved(const base::FilePath& profile_path,
                                    const string16& profile_name) OVERRIDE;
-  virtual void OnProfileNameChanged(const FilePath& profile_path,
+  virtual void OnProfileNameChanged(const base::FilePath& profile_path,
                                     const string16& old_profile_name) OVERRIDE;
-  virtual void OnProfileAvatarChanged(const FilePath& profile_path) OVERRIDE;
+  virtual void OnProfileAvatarChanged(const base::FilePath& profile_path) OVERRIDE;
 
   // Overridden from ProfileSyncServiceObserver:
   virtual void OnStateChanged() OVERRIDE;
diff --git a/chrome/browser/ui/cocoa/download/download_util_mac.h b/chrome/browser/ui/cocoa/download/download_util_mac.h
index 968f1a1cb4ad99..b873cc8eadeec9 100644
--- a/chrome/browser/ui/cocoa/download/download_util_mac.h
+++ b/chrome/browser/ui/cocoa/download/download_util_mac.h
@@ -9,11 +9,13 @@
 
 #import <Cocoa/Cocoa.h>
 
+namespace base {
 class FilePath;
+}
 
 namespace download_util {
 
-void AddFileToPasteboard(NSPasteboard* pasteboard, const FilePath& path);
+void AddFileToPasteboard(NSPasteboard* pasteboard, const base::FilePath& path);
 
 }  // namespace download_util
 
diff --git a/chrome/browser/ui/hung_plugin_tab_helper.h b/chrome/browser/ui/hung_plugin_tab_helper.h
index 0cf6b336f1314d..51feb42de24d8e 100644
--- a/chrome/browser/ui/hung_plugin_tab_helper.h
+++ b/chrome/browser/ui/hung_plugin_tab_helper.h
@@ -17,9 +17,12 @@
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
-class FilePath;
 class InfoBarDelegate;
 
+namespace base {
+class FilePath;
+}
+
 // Manages per-tab state with regard to hung plugins. This only handles
 // Pepper plugins which we know are windowless. Hung NPAPI plugins (which
 // may have native windows) can not be handled with infobars and have a
@@ -40,10 +43,10 @@ class HungPluginTabHelper
   virtual ~HungPluginTabHelper();
 
   // content::WebContentsObserver overrides:
-  virtual void PluginCrashed(const FilePath& plugin_path,
+  virtual void PluginCrashed(const base::FilePath& plugin_path,
                              base::ProcessId plugin_pid) OVERRIDE;
   virtual void PluginHungStatusChanged(int plugin_child_id,
-                                       const FilePath& plugin_path,
+                                       const base::FilePath& plugin_path,
                                        bool is_hung) OVERRIDE;
 
   // NotificationObserver overrides.
@@ -64,10 +67,10 @@ class HungPluginTabHelper
   // not we're currently showing the infobar.
   struct PluginState {
     // Initializes the plugin state to be a hung plugin.
-    PluginState(const FilePath& p, const string16& n);
+    PluginState(const base::FilePath& p, const string16& n);
     ~PluginState();
 
-    FilePath path;
+    base::FilePath path;
     string16 name;
 
     // Possibly-null if we're not showing an infobar right now.
diff --git a/chrome/browser/ui/network_profile_bubble.h b/chrome/browser/ui/network_profile_bubble.h
index 7829539b1844e6..74eb2facbb442a 100644
--- a/chrome/browser/ui/network_profile_bubble.h
+++ b/chrome/browser/ui/network_profile_bubble.h
@@ -8,10 +8,13 @@
 #include "base/basictypes.h"
 
 class Browser;
-class FilePath;
 class PrefServiceSyncable;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 // This class will try to detect if the profile is on a network share and if
 // this is the case notify the user with an info bubble.
 class NetworkProfileBubble {
@@ -47,7 +50,7 @@ class NetworkProfileBubble {
 
   // Verifies that the profile folder is not located on a network share, and if
   // it is shows the warning bubble to the user.
-  static void CheckNetworkProfile(const FilePath& profile_folder);
+  static void CheckNetworkProfile(const base::FilePath& profile_folder);
 
   // Shows the notification bubble using the provided |browser|.
   static void ShowNotification(Browser* browser);
diff --git a/chrome/browser/ui/startup/startup_browser_creator_impl.h b/chrome/browser/ui/startup/startup_browser_creator_impl.h
index 73806e32fdd20e..4a0905c87140c5 100644
--- a/chrome/browser/ui/startup/startup_browser_creator_impl.h
+++ b/chrome/browser/ui/startup/startup_browser_creator_impl.h
@@ -16,10 +16,13 @@
 
 class Browser;
 class CommandLine;
-class FilePath;
 class Profile;
 class StartupBrowserCreator;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class WebContents;
 }
@@ -40,10 +43,10 @@ class StartupBrowserCreatorImpl {
   // and thus no access to distribution-specific first-run behaviors. The
   // second one is always called when the browser starts even if it is not
   // the first run.  |is_first_run| indicates that this is a new profile.
-  StartupBrowserCreatorImpl(const FilePath& cur_dir,
+  StartupBrowserCreatorImpl(const base::FilePath& cur_dir,
                             const CommandLine& command_line,
                             chrome::startup::IsFirstRun is_first_run);
-  StartupBrowserCreatorImpl(const FilePath& cur_dir,
+  StartupBrowserCreatorImpl(const base::FilePath& cur_dir,
                             const CommandLine& command_line,
                             StartupBrowserCreator* browser_creator,
                             chrome::startup::IsFirstRun is_first_run);
@@ -148,7 +151,7 @@ class StartupBrowserCreatorImpl {
       Profile* profile,
       const std::vector<GURL>& startup_urls);
 
-  const FilePath cur_dir_;
+  const base::FilePath cur_dir_;
   const CommandLine& command_line_;
   Profile* profile_;
   StartupBrowserCreator* browser_creator_;
diff --git a/chrome/browser/ui/user_data_dir_dialog.h b/chrome/browser/ui/user_data_dir_dialog.h
index 7b25933a08e9eb..eb8418ed79247f 100644
--- a/chrome/browser/ui/user_data_dir_dialog.h
+++ b/chrome/browser/ui/user_data_dir_dialog.h
@@ -5,7 +5,9 @@
 #ifndef CHROME_BROWSER_UI_USER_DATA_DIR_DIALOG_H_
 #define CHROME_BROWSER_UI_USER_DATA_DIR_DIALOG_H_
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
@@ -13,7 +15,7 @@ namespace chrome {
 // is showing. If the user picks a directory, this method returns the chosen
 // directory. |user_data_dir| is the value of the directory we were not able to
 // use.
-FilePath ShowUserDataDirDialog(const FilePath& user_data_dir);
+base::FilePath ShowUserDataDirDialog(const base::FilePath& user_data_dir);
 
 }  // namespace chrome
 
diff --git a/chrome/browser/ui/webui/extensions/extension_settings_handler.h b/chrome/browser/ui/webui/extensions/extension_settings_handler.h
index 82acd58b6141b1..4ba5a3d34c089f 100644
--- a/chrome/browser/ui/webui/extensions/extension_settings_handler.h
+++ b/chrome/browser/ui/webui/extensions/extension_settings_handler.h
@@ -28,11 +28,11 @@
 #include "ui/shell_dialogs/select_file_dialog.h"
 
 class ExtensionService;
-class FilePath;
 class PrefServiceSyncable;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 class ListValue;
 }
 
@@ -104,10 +104,10 @@ class ExtensionSettingsHandler
   virtual void RegisterMessages() OVERRIDE;
 
   // SelectFileDialog::Listener implementation.
-  virtual void FileSelected(const FilePath& path,
+  virtual void FileSelected(const base::FilePath& path,
                             int index, void* params) OVERRIDE;
   virtual void MultiFilesSelected(
-      const std::vector<FilePath>& files, void* params) OVERRIDE;
+      const std::vector<base::FilePath>& files, void* params) OVERRIDE;
   virtual void FileSelectionCanceled(void* params) OVERRIDE {}
 
   // content::NotificationObserver implementation.
@@ -218,7 +218,7 @@ class ExtensionSettingsHandler
 
   // Used to start the |load_extension_dialog_| in the last directory that was
   // loaded.
-  FilePath last_unpacked_directory_;
+  base::FilePath last_unpacked_directory_;
 
   // Used to show confirmation UI for uninstalling extensions in incognito mode.
   scoped_ptr<ExtensionUninstallDialog> extension_uninstall_dialog_;
diff --git a/chrome/browser/ui/webui/feedback_ui.h b/chrome/browser/ui/webui/feedback_ui.h
index 1aef9580708855..4bef57d3216a75 100644
--- a/chrome/browser/ui/webui/feedback_ui.h
+++ b/chrome/browser/ui/webui/feedback_ui.h
@@ -10,7 +10,9 @@
 #include "base/basictypes.h"
 #include "ui/web_dialogs/web_dialog_ui.h"
 
+namespace base {
 class FilePath;
+}
 
 class FeedbackUI : public ui::WebDialogUI {
  public:
@@ -18,7 +20,7 @@ class FeedbackUI : public ui::WebDialogUI {
 
 #if defined(OS_CHROMEOS)
   static void GetMostRecentScreenshots(
-      const FilePath& filepath,
+      const base::FilePath& filepath,
       std::vector<std::string>* saved_screenshots,
       size_t max_saved);
 #endif
diff --git a/chrome/browser/ui/webui/print_preview/print_preview_handler.h b/chrome/browser/ui/webui/print_preview/print_preview_handler.h
index 5be2f944937e68..553ecffc47e89e 100644
--- a/chrome/browser/ui/webui/print_preview/print_preview_handler.h
+++ b/chrome/browser/ui/webui/print_preview/print_preview_handler.h
@@ -17,11 +17,11 @@
 #include "printing/print_job_constants.h"
 #include "ui/shell_dialogs/select_file_dialog.h"
 
-class FilePath;
 class PrintSystemTaskProxy;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 class RefCountedBytes;
 }
 
@@ -48,7 +48,7 @@ class PrintPreviewHandler : public content::WebUIMessageHandler,
   virtual void RegisterMessages() OVERRIDE;
 
   // SelectFileDialog::Listener implementation.
-  virtual void FileSelected(const FilePath& path,
+  virtual void FileSelected(const base::FilePath& path,
                             int index,
                             void* params) OVERRIDE;
   virtual void FileSelectionCanceled(void* params) OVERRIDE;
@@ -57,7 +57,7 @@ class PrintPreviewHandler : public content::WebUIMessageHandler,
   virtual void OnPrintDialogShown() OVERRIDE;
 
   // Displays a modal dialog, prompting the user to select a file.
-  void SelectFile(const FilePath& default_path);
+  void SelectFile(const base::FilePath& default_path);
 
   // Called when the print preview dialog is destroyed. This is the last time
   // this object has access to the PrintViewManager in order to disconnect the
@@ -220,7 +220,7 @@ class PrintPreviewHandler : public content::WebUIMessageHandler,
 
   // Holds the path to the print to pdf request. It is empty if no such request
   // exists.
-  scoped_ptr<FilePath> print_to_pdf_path_;
+  scoped_ptr<base::FilePath> print_to_pdf_path_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewHandler);
 };
diff --git a/chrome/browser/ui/webui/print_preview/sticky_settings.h b/chrome/browser/ui/webui/print_preview/sticky_settings.h
index ab3395d9b76aab..77a4c10745b5cc 100644
--- a/chrome/browser/ui/webui/print_preview/sticky_settings.h
+++ b/chrome/browser/ui/webui/print_preview/sticky_settings.h
@@ -11,13 +11,13 @@
 
 #include "base/memory/scoped_ptr.h"
 
-class FilePath;
 class PrintPreviewHandlerTest;
 class PrefService;
 class PrefServiceSyncable;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace printing {
@@ -30,20 +30,20 @@ class StickySettings {
   StickySettings();
   ~StickySettings();
 
-  FilePath* save_path();
+  base::FilePath* save_path();
   std::string* printer_app_state();
 
   // Stores app state for the last used printer.
   void StoreAppState(const std::string& app_state);
   // Stores the last path the user used to save to pdf.
-  void StoreSavePath(const FilePath& path);
+  void StoreSavePath(const base::FilePath& path);
 
   void SaveInPrefs(PrefService* profile);
   void RestoreFromPrefs(PrefService* profile);
   static void RegisterUserPrefs(PrefServiceSyncable* prefs);
  private:
 
-  scoped_ptr<FilePath> save_path_;
+  scoped_ptr<base::FilePath> save_path_;
   scoped_ptr<std::string> printer_app_state_;
 };
 
diff --git a/chrome/browser/ui/webui/screenshot_source.h b/chrome/browser/ui/webui/screenshot_source.h
index 4c7c0c581711f5..30d80f40bf6366 100644
--- a/chrome/browser/ui/webui/screenshot_source.h
+++ b/chrome/browser/ui/webui/screenshot_source.h
@@ -23,9 +23,12 @@
 typedef std::vector<unsigned char> ScreenshotData;
 typedef linked_ptr<ScreenshotData> ScreenshotDataPtr;
 
-class FilePath;
 class Profile;
 
+namespace base {
+class FilePath;
+}
+
 // ScreenshotSource is the data source that serves screenshots (saved
 // or current) to the bug report html ui.
 class ScreenshotSource : public content::URLDataSource {
@@ -40,7 +43,7 @@ class ScreenshotSource : public content::URLDataSource {
 
   // Common access for the screenshot directory, parameter is set to the
   // requested directory and return value of true is given upon success.
-  static bool GetScreenshotDirectory(FilePath* directory);
+  static bool GetScreenshotDirectory(base::FilePath* directory);
 #endif
 
   // Get the basefilename for screenshots
@@ -89,14 +92,14 @@ class ScreenshotSource : public content::URLDataSource {
   void SendSavedScreenshot(
       const std::string& screenshot_path,
       const content::URLDataSource::GotDataCallback& callback,
-      const FilePath& file);
+      const base::FilePath& file);
 
   // The callback for Drive's getting file method.
   void GetSavedScreenshotCallback(
       const std::string& screenshot_path,
       const content::URLDataSource::GotDataCallback& callback,
       drive::DriveFileError error,
-      const FilePath& file,
+      const base::FilePath& file,
       const std::string& unused_mime_type,
       drive::DriveFileType file_type);
 
diff --git a/chrome/browser/value_store/value_store_frontend.h b/chrome/browser/value_store/value_store_frontend.h
index 19c0f23e93ae47..0a4c0ba447ffa3 100644
--- a/chrome/browser/value_store/value_store_frontend.h
+++ b/chrome/browser/value_store/value_store_frontend.h
@@ -14,9 +14,12 @@
 #include "base/threading/non_thread_safe.h"
 #include "base/values.h"
 
-class FilePath;
 class ValueStore;
 
+namespace base {
+class FilePath;
+}
+
 // A frontend for a LeveldbValueStore, for use on the UI thread.
 class ValueStoreFrontend
     : public base::SupportsWeakPtr<ValueStoreFrontend>,
@@ -25,12 +28,12 @@ class ValueStoreFrontend
   typedef base::Callback<void(scoped_ptr<base::Value>)> ReadCallback;
 
   ValueStoreFrontend();
-  explicit ValueStoreFrontend(const FilePath& db_path);
+  explicit ValueStoreFrontend(const base::FilePath& db_path);
   // This variant is useful for testing (using a mock ValueStore).
   explicit ValueStoreFrontend(ValueStore* value_store);
   ~ValueStoreFrontend();
 
-  void Init(const FilePath& db_path);
+  void Init(const base::FilePath& db_path);
 
   // Retrieves a value from the database asynchronously, passing a copy to
   // |callback| when ready. NULL is passed if no matching entry is found.
diff --git a/chrome/browser/webdata/web_database.cc b/chrome/browser/webdata/web_database.cc
index 48316dae7d8dce..a645d4dc329730 100644
--- a/chrome/browser/webdata/web_database.cc
+++ b/chrome/browser/webdata/web_database.cc
@@ -89,7 +89,7 @@ sql::Connection* WebDatabase::GetSQLConnection() {
   return &db_;
 }
 
-sql::InitStatus WebDatabase::Init(const FilePath& db_name,
+sql::InitStatus WebDatabase::Init(const base::FilePath& db_name,
                                   const std::string& app_locale) {
   // When running in unit tests, there is already a NotificationService object.
   // Since only one can exist at a time per thread, check first.
diff --git a/chrome/browser/webdata/web_database.h b/chrome/browser/webdata/web_database.h
index d384e654c915a7..273148e3f55161 100644
--- a/chrome/browser/webdata/web_database.h
+++ b/chrome/browser/webdata/web_database.h
@@ -11,13 +11,16 @@
 #include "sql/meta_table.h"
 
 class AutofillTable;
-class FilePath;
 class KeywordTable;
 class LoginsTable;
 class TokenServiceTable;
 class WebAppsTable;
 class WebIntentsTable;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 class NotificationService;
 }
@@ -35,7 +38,7 @@ class WebDatabase {
   // file is. If this returns an error code, no other method should be called.
   // Requires the |app_locale| to be passed as a parameter as the locale can
   // only safely be queried on the UI thread.
-  sql::InitStatus Init(const FilePath& db_name, const std::string& app_locale);
+  sql::InitStatus Init(const base::FilePath& db_name, const std::string& app_locale);
 
   // Transactions management
   void BeginTransaction();
diff --git a/chrome/common/chrome_paths_internal.h b/chrome/common/chrome_paths_internal.h
index 1d91a6ff4a2f6f..5f9b18b9e13ae0 100644
--- a/chrome/common/chrome_paths_internal.h
+++ b/chrome/common/chrome_paths_internal.h
@@ -17,18 +17,20 @@ class NSBundle;
 #endif
 #endif
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 
 // Get the path to the user's data directory, regardless of whether
 // DIR_USER_DATA has been overridden by a command-line option.
-bool GetDefaultUserDataDirectory(FilePath* result);
+bool GetDefaultUserDataDirectory(base::FilePath* result);
 
 // This returns the base directory in which Chrome Frame stores user profiles.
 // Note that this cannot be wrapped in a preprocessor define since
 // CF and Google Chrome want to share the same binaries.
-bool GetChromeFrameUserDataDirectory(FilePath* result);
+bool GetChromeFrameUserDataDirectory(base::FilePath* result);
 
 // Get the path to the user's cache directory.  This is normally the
 // same as the profile directory, but on Linux it can also be
@@ -37,54 +39,54 @@ bool GetChromeFrameUserDataDirectory(FilePath* result);
 // of this directory, with names like "Cache" and "Media Cache".
 // This will always fill in |result| with a directory, sometimes
 // just |profile_dir|.
-void GetUserCacheDirectory(const FilePath& profile_dir, FilePath* result);
+void GetUserCacheDirectory(const base::FilePath& profile_dir, base::FilePath* result);
 
 // Get the path to the user's documents directory.
-bool GetUserDocumentsDirectory(FilePath* result);
+bool GetUserDocumentsDirectory(base::FilePath* result);
 
 #if defined(OS_WIN) || defined(OS_LINUX)
 // Gets the path to a safe default download directory for a user.
-bool GetUserDownloadsDirectorySafe(FilePath* result);
+bool GetUserDownloadsDirectorySafe(base::FilePath* result);
 #endif
 
 // Get the path to the user's downloads directory.
-bool GetUserDownloadsDirectory(FilePath* result);
+bool GetUserDownloadsDirectory(base::FilePath* result);
 
 // Gets the path to the user's music directory.
-bool GetUserMusicDirectory(FilePath* result);
+bool GetUserMusicDirectory(base::FilePath* result);
 
 // Gets the path to the user's pictures directory.
-bool GetUserPicturesDirectory(FilePath* result);
+bool GetUserPicturesDirectory(base::FilePath* result);
 
 // Gets the path to the user's videos directory.
-bool GetUserVideosDirectory(FilePath* result);
+bool GetUserVideosDirectory(base::FilePath* result);
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
 // The "versioned directory" is a directory in the browser .app bundle.  It
 // contains the bulk of the application, except for the things that the system
 // requires be located at spepcific locations.  The versioned directory is
 // in the .app at Contents/Versions/w.x.y.z.
-FilePath GetVersionedDirectory();
+base::FilePath GetVersionedDirectory();
 
 // This overrides the directory returned by |GetVersionedDirectory()|, to be
 // used when |GetVersionedDirectory()| can't automatically determine the proper
 // location. This is the case when the browser didn't load itself but by, e.g.,
 // the app mode loader. This should be called before |ChromeMain()|. This takes
 // ownership of the object |path| and the caller must not delete it.
-void SetOverrideVersionedDirectory(const FilePath* path);
+void SetOverrideVersionedDirectory(const base::FilePath* path);
 
 // Most of the application is further contained within the framework.  The
 // framework bundle is located within the versioned directory at a specific
 // path.  The only components in the versioned directory not included in the
 // framework are things that also depend on the framework, such as the helper
 // app bundle.
-FilePath GetFrameworkBundlePath();
+base::FilePath GetFrameworkBundlePath();
 
 // Get the local library directory.
-bool GetLocalLibraryDirectory(FilePath* result);
+bool GetLocalLibraryDirectory(base::FilePath* result);
 
 // Get the global Application Support directory (under /Library/).
-bool GetGlobalApplicationSupportDirectory(FilePath* result);
+bool GetGlobalApplicationSupportDirectory(base::FilePath* result);
 
 // Returns the NSBundle for the outer browser application, even when running
 // inside the helper. In unbundled applications, such as tests, returns nil.
diff --git a/chrome/common/dump_without_crashing.cc b/chrome/common/dump_without_crashing.cc
index 8c692e49c7b21f..75023d9e7d013e 100644
--- a/chrome/common/dump_without_crashing.cc
+++ b/chrome/common/dump_without_crashing.cc
@@ -6,6 +6,7 @@
 
 #include "chrome/common/dump_without_crashing.h"
 
+#include "base/logging.h"
 #include "chrome/common/chrome_constants.h"
 
 #if defined(OS_WIN)
diff --git a/chrome/common/extensions/extension_file_util.h b/chrome/common/extensions/extension_file_util.h
index 339c90b08e0e8e..430ec383a3a874 100644
--- a/chrome/common/extensions/extension_file_util.h
+++ b/chrome/common/extensions/extension_file_util.h
@@ -12,11 +12,11 @@
 #include "chrome/common/extensions/manifest.h"
 #include "chrome/common/extensions/message_bundle.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace extensions {
@@ -31,26 +31,26 @@ namespace extension_file_util {
 // Copies |unpacked_source_dir| into the right location under |extensions_dir|.
 // The destination directory is returned on success, or empty path is returned
 // on failure.
-FilePath InstallExtension(const FilePath& unpacked_source_dir,
-                          const std::string& id,
-                          const std::string& version,
-                          const FilePath& extensions_dir);
+base::FilePath InstallExtension(const base::FilePath& unpacked_source_dir,
+                                const std::string& id,
+                                const std::string& version,
+                                const base::FilePath& extensions_dir);
 
 // Removes all versions of the extension with |id| from |extensions_dir|.
-void UninstallExtension(const FilePath& extensions_dir,
+void UninstallExtension(const base::FilePath& extensions_dir,
                         const std::string& id);
 
 // Loads and validates an extension from the specified directory. Returns NULL
 // on failure, with a description of the error in |error|.
 scoped_refptr<extensions::Extension> LoadExtension(
-    const FilePath& extension_root,
+    const base::FilePath& extension_root,
     extensions::Manifest::Location location,
     int flags,
     std::string* error);
 
 // The same as LoadExtension except use the provided |extension_id|.
 scoped_refptr<extensions::Extension> LoadExtension(
-    const FilePath& extension_root,
+    const base::FilePath& extension_root,
     const std::string& extension_id,
     extensions::Manifest::Location location,
     int flags,
@@ -58,11 +58,11 @@ scoped_refptr<extensions::Extension> LoadExtension(
 
 // Loads an extension manifest from the specified directory. Returns NULL
 // on failure, with a description of the error in |error|.
-base::DictionaryValue* LoadManifest(const FilePath& extension_root,
+base::DictionaryValue* LoadManifest(const base::FilePath& extension_root,
                                     std::string* error);
 
 // Returns true if the given file path exists and is not zero-length.
-bool ValidateFilePath(const FilePath& path);
+bool ValidateFilePath(const base::FilePath& path);
 
 // Returns true if the given extension object is valid and consistent.
 // May also append a series of warning messages to |warnings|, but they
@@ -75,7 +75,7 @@ bool ValidateExtension(const extensions::Extension* extension,
                        std::vector<extensions::InstallWarning>* warnings);
 
 // Returns a list of files that contain private keys inside |extension_dir|.
-std::vector<FilePath> FindPrivateKeyFiles(const FilePath& extension_dir);
+std::vector<base::FilePath> FindPrivateKeyFiles(const base::FilePath& extension_dir);
 
 // Cleans up the extension install directory. It can end up with garbage in it
 // if extensions can't initially be removed when they are uninstalled (eg if a
@@ -87,20 +87,20 @@ std::vector<FilePath> FindPrivateKeyFiles(const FilePath& extension_dir);
 // Obsolete version directories are removed, as are directories that aren't
 // found in |extension_paths|.
 void GarbageCollectExtensions(
-    const FilePath& extensions_dir,
-    const std::multimap<std::string, FilePath>& extension_paths);
+    const base::FilePath& extensions_dir,
+    const std::multimap<std::string, base::FilePath>& extension_paths);
 
 // Loads extension message catalogs and returns message bundle.
 // Returns NULL on error, or if extension is not localized.
 extensions::MessageBundle* LoadMessageBundle(
-    const FilePath& extension_path,
+    const base::FilePath& extension_path,
     const std::string& default_locale,
     std::string* error);
 
 // Loads the extension message bundle substitution map. Contains at least
 // extension_id item.
 extensions::MessageBundle::SubstitutionMap* LoadMessageBundleSubstitutionMap(
-    const FilePath& extension_path,
+    const base::FilePath& extension_path,
     const std::string& extension_id,
     const std::string& default_locale);
 
@@ -108,27 +108,28 @@ extensions::MessageBundle::SubstitutionMap* LoadMessageBundleSubstitutionMap(
 // use by Chrome.
 // If any files or directories are found using "_" prefix and are not on
 // reserved list we return false, and set error message.
-bool CheckForIllegalFilenames(const FilePath& extension_path,
+bool CheckForIllegalFilenames(const base::FilePath& extension_path,
                               std::string* error);
 
 // Get a relative file path from a chrome-extension:// URL.
-FilePath ExtensionURLToRelativeFilePath(const GURL& url);
+base::FilePath ExtensionURLToRelativeFilePath(const GURL& url);
 
 // Get a full file path from a chrome-extension-resource:// URL, If the URL
 // points a file outside of root, this function will return empty FilePath.
-FilePath ExtensionResourceURLToFilePath(const GURL& url, const FilePath& root);
+base::FilePath ExtensionResourceURLToFilePath(const GURL& url,
+                                              const base::FilePath& root);
 
 // Returns a path to a temporary directory for unpacking an extension that will
 // be installed into |extensions_dir|. Creates the directory if necessary.
 // The directory will be on the same file system as |extensions_dir| so
 // that the extension directory can be efficiently renamed into place. Returns
 // an empty file path on failure.
-FilePath GetInstallTempDir(const FilePath& extensions_dir);
+base::FilePath GetInstallTempDir(const base::FilePath& extensions_dir);
 
 // Helper function to delete files. This is used to avoid ugly casts which
 // would be necessary with PostMessage since file_util::Delete is overloaded.
 // TODO(skerner): Make a version of Delete that is not overloaded in file_util.
-void DeleteFile(const FilePath& path, bool recursive);
+void DeleteFile(const base::FilePath& path, bool recursive);
 
 }  // namespace extension_file_util
 
diff --git a/chrome/common/extensions/extension_l10n_util.h b/chrome/common/extensions/extension_l10n_util.h
index 24178a076fc4b5..ad908928bfe64b 100644
--- a/chrome/common/extensions/extension_l10n_util.h
+++ b/chrome/common/extensions/extension_l10n_util.h
@@ -11,10 +11,9 @@
 #include <string>
 #include <vector>
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace extensions {
@@ -46,7 +45,7 @@ bool LocalizeManifest(const extensions::MessageBundle& messages,
 
 // Load message catalogs, localize manifest and attach message bundle to the
 // extension.
-bool LocalizeExtension(const FilePath& extension_path,
+bool LocalizeExtension(const base::FilePath& extension_path,
                        base::DictionaryValue* manifest,
                        std::string* error);
 
@@ -56,7 +55,7 @@ bool LocalizeExtension(const FilePath& extension_path,
 // error with locale_name.
 // If file name starts with . return true (helps testing extensions under svn).
 bool AddLocale(const std::set<std::string>& chrome_locales,
-               const FilePath& locale_folder,
+               const base::FilePath& locale_folder,
                const std::string& locale_name,
                std::set<std::string>* valid_locales,
                std::string* error);
@@ -82,7 +81,7 @@ void GetAllFallbackLocales(const std::string& application_locale,
 // 4. Intersect both lists, and add intersection to the extension.
 // Returns false if any of supplied locales don't match chrome list of locales.
 // Fills out error with offending locale name.
-bool GetValidLocales(const FilePath& locale_path,
+bool GetValidLocales(const base::FilePath& locale_path,
                      std::set<std::string>* locales,
                      std::string* error);
 
@@ -92,7 +91,7 @@ bool GetValidLocales(const FilePath& locale_path,
 // Returns message bundle if it can load default locale messages file, and all
 // messages are valid, else returns NULL and sets error.
 extensions::MessageBundle* LoadMessageCatalogs(
-    const FilePath& locale_path,
+    const base::FilePath& locale_path,
     const std::string& default_locale,
     const std::string& app_locale,
     const std::set<std::string>& valid_locales,
@@ -103,8 +102,8 @@ extensions::MessageBundle* LoadMessageCatalogs(
 // |locales_path| is extension_id/_locales
 // |locale_path| is extension_id/_locales/xx
 // |all_locales| is a set of all valid Chrome locales.
-bool ShouldSkipValidation(const FilePath& locales_path,
-                          const FilePath& locale_path,
+bool ShouldSkipValidation(const base::FilePath& locales_path,
+                          const base::FilePath& locale_path,
                           const std::set<std::string>& all_locales);
 
 // Sets the process locale for the duration of the current scope, then reverts
diff --git a/chrome/common/logging_chrome.h b/chrome/common/logging_chrome.h
index dee2533671233e..bde1793f793b6d 100644
--- a/chrome/common/logging_chrome.h
+++ b/chrome/common/logging_chrome.h
@@ -12,7 +12,10 @@
 #include "base/time.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace logging {
 
@@ -34,7 +37,7 @@ void InitChromeLogging(const CommandLine& command_line,
 
 #if defined(OS_CHROMEOS)
 // Get the log file location.
-FilePath GetSessionLogFile(const CommandLine& command_line);
+base::FilePath GetSessionLogFile(const CommandLine& command_line);
 
 // Redirects chrome logging to the appropriate session log dir.
 void RedirectChromeLogging(const CommandLine& command_line);
@@ -44,7 +47,7 @@ void RedirectChromeLogging(const CommandLine& command_line);
 void CleanupChromeLogging();
 
 // Returns the fully-qualified name of the log file.
-FilePath GetLogFileName();
+base::FilePath GetLogFileName();
 
 // Returns true when error/assertion dialogs are to be shown,
 // false otherwise.
@@ -64,8 +67,8 @@ size_t GetFatalAssertions(AssertionList* assertions);
 
 // Inserts timestamp before file extension in the format
 // "_yymmdd-hhmmss".
-FilePath GenerateTimestampedName(const FilePath& base_path,
-                                 base::Time timestamp);
+base::FilePath GenerateTimestampedName(const base::FilePath& base_path,
+                                       base::Time timestamp);
 }  // namespace logging
 
 #endif  // CHROME_COMMON_LOGGING_CHROME_H_
diff --git a/chrome/common/mac/app_mode_chrome_locator.h b/chrome/common/mac/app_mode_chrome_locator.h
index 860298c2a1cc39..e7da4c43cc6f40 100644
--- a/chrome/common/mac/app_mode_chrome_locator.h
+++ b/chrome/common/mac/app_mode_chrome_locator.h
@@ -11,13 +11,15 @@
 
 @class NSString;
 
+namespace base {
 class FilePath;
+}
 
 namespace app_mode {
 
 // Given a bundle id, return the path of the corresponding bundle.
 // Returns true if the bundle was found, false otherwise.
-bool FindBundleById(NSString* bundle_id, FilePath* out_bundle);
+bool FindBundleById(NSString* bundle_id, base::FilePath* out_bundle);
 
 // Given the path to the Chrome bundle, read the following information:
 // |raw_version_str| - Chrome version.
@@ -25,10 +27,10 @@ bool FindBundleById(NSString* bundle_id, FilePath* out_bundle);
 // |framework_shlib_path| - Path to the chrome framework's shared library (not
 //                          the framework directory).
 // Returns true if all information read succesfuly, false otherwise.
-bool GetChromeBundleInfo(const FilePath& chrome_bundle,
+bool GetChromeBundleInfo(const base::FilePath& chrome_bundle,
                          string16* raw_version_str,
-                         FilePath* version_path,
-                         FilePath* framework_shlib_path);
+                         base::FilePath* version_path,
+                         base::FilePath* framework_shlib_path);
 
 }  // namespace app_mode
 
diff --git a/chrome/common/spellcheck_common.h b/chrome/common/spellcheck_common.h
index 55f82720c9035f..c2d84984b5cdb7 100644
--- a/chrome/common/spellcheck_common.h
+++ b/chrome/common/spellcheck_common.h
@@ -8,7 +8,9 @@
 #include <string>
 #include <vector>
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome {
 namespace spellcheck_common {
@@ -28,8 +30,8 @@ static const size_t MAX_CUSTOM_DICTIONARY_WORD_BYTES = 99;
 
 typedef std::vector<std::string> WordList;
 
-FilePath GetVersionedFileName(const std::string& input_language,
-                              const FilePath& dict_dir);
+base::FilePath GetVersionedFileName(const std::string& input_language,
+                                    const base::FilePath& dict_dir);
 
 std::string GetCorrespondingSpellCheckLanguage(const std::string& language);
 
diff --git a/chrome/installer/launcher_support/chrome_launcher_support.h b/chrome/installer/launcher_support/chrome_launcher_support.h
index caca2a5006fc8e..ea4d12ed01e7c2 100644
--- a/chrome/installer/launcher_support/chrome_launcher_support.h
+++ b/chrome/installer/launcher_support/chrome_launcher_support.h
@@ -5,7 +5,9 @@
 #ifndef CHROME_INSTALLER_LAUNCHER_SUPPORT_CHROME_LAUNCHER_SUPPORT_H_
 #define CHROME_INSTALLER_LAUNCHER_SUPPORT_CHROME_LAUNCHER_SUPPORT_H_
 
+namespace base {
 class FilePath;
+}
 
 namespace chrome_launcher_support {
 
@@ -16,17 +18,17 @@ enum InstallationLevel {
 
 // Returns the path to an existing setup.exe at the specified level, if it can
 // be found via Omaha client state.
-FilePath GetSetupExeForInstallationLevel(InstallationLevel level);
+base::FilePath GetSetupExeForInstallationLevel(InstallationLevel level);
 
 // Returns the path to an installed chrome.exe at the specified level, if it can
 // be found via Omaha client state. Prefers the installer from a multi-install,
 // but may also return that of a single-install of Chrome if no multi-install
 // exists.
-FilePath GetChromePathForInstallationLevel(InstallationLevel level);
+base::FilePath GetChromePathForInstallationLevel(InstallationLevel level);
 
 // Returns the path to an installed app_host.exe at the specified level, if
 // it can be found via Omaha client state.
-FilePath GetAppHostPathForInstallationLevel(InstallationLevel level);
+base::FilePath GetAppHostPathForInstallationLevel(InstallationLevel level);
 
 // Returns the path to an installed chrome.exe, or an empty path. Prefers a
 // system-level installation to a user-level installation. Uses Omaha client
@@ -34,7 +36,7 @@ FilePath GetAppHostPathForInstallationLevel(InstallationLevel level);
 // In non-official builds, to ease development, this will first look for a
 // chrome.exe in the same directory as the current executable.
 // The file path returned (if any) is guaranteed to exist.
-FilePath GetAnyChromePath();
+base::FilePath GetAnyChromePath();
 
 // Returns the path to an installed app_host.exe, or an empty path. Prefers a
 // system-level installation to a user-level installation. Uses Omaha client
@@ -42,7 +44,7 @@ FilePath GetAnyChromePath();
 // In non-official builds, to ease development, this will first look for a
 // app_host.exe in the same directory as the current executable.
 // The file path returned (if any) is guaranteed to exist.
-FilePath GetAnyAppHostPath();
+base::FilePath GetAnyAppHostPath();
 
 // Returns true if App Host is installed (system-level or user-level),
 // or in the same directory as the current executable.
diff --git a/chrome/installer/setup/install.h b/chrome/installer/setup/install.h
index abf0ab3698c227..4ce974b5c0026f 100644
--- a/chrome/installer/setup/install.h
+++ b/chrome/installer/setup/install.h
@@ -17,7 +17,9 @@
 #include "chrome/installer/util/product.h"
 #include "chrome/installer/util/util_constants.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
@@ -55,7 +57,7 @@ void EscapeXmlAttributeValueInSingleQuotes(string16* att_value);
 // Creates VisualElementsManifest.xml beside chrome.exe in |src_path| if
 // |src_path|\VisualElements exists.
 // Returns true unless the manifest is supposed to be created, but fails to be.
-bool CreateVisualElementsManifest(const FilePath& src_path,
+bool CreateVisualElementsManifest(const base::FilePath& src_path,
                                   const Version& version);
 
 // Overwrites shortcuts (desktop, quick launch, and start menu) if they are
@@ -71,7 +73,7 @@ bool CreateVisualElementsManifest(const FilePath& src_path,
 // If creating the Start menu shortcut is successful, it is also pinned to the
 // taskbar.
 void CreateOrUpdateShortcuts(
-    const FilePath& target,
+    const base::FilePath& target,
     const Product& product,
     const MasterPreferences& prefs,
     InstallShortcutLevel install_level,
@@ -107,11 +109,11 @@ void RegisterChromeOnMachine(const InstallerState& installer_state,
 InstallStatus InstallOrUpdateProduct(
     const InstallationState& original_state,
     const InstallerState& installer_state,
-    const FilePath& setup_path,
-    const FilePath& archive_path,
-    const FilePath& install_temp_path,
-    const FilePath& src_path,
-    const FilePath& prefs_path,
+    const base::FilePath& setup_path,
+    const base::FilePath& archive_path,
+    const base::FilePath& install_temp_path,
+    const base::FilePath& src_path,
+    const base::FilePath& prefs_path,
     const installer::MasterPreferences& prefs,
     const Version& new_version);
 
@@ -127,7 +129,7 @@ void HandleOsUpgradeForBrowser(const InstallerState& installer_state,
 // Shortcut creation is skipped if the First Run beacon is present (unless
 // |force| is set to true).
 // |chrome| The installed product (must be a browser).
-void HandleActiveSetupForBrowser(const FilePath& installation_root,
+void HandleActiveSetupForBrowser(const base::FilePath& installation_root,
                                  const Product& chrome,
                                  bool force);
 
diff --git a/chrome/installer/setup/install_worker.h b/chrome/installer/setup/install_worker.h
index a9d59b3f873478..7c96302638f41a 100644
--- a/chrome/installer/setup/install_worker.h
+++ b/chrome/installer/setup/install_worker.h
@@ -14,10 +14,13 @@
 
 class BrowserDistribution;
 class CommandLine;
-class FilePath;
 class Version;
 class WorkItemList;
 
+namespace base {
+class FilePath;
+}
+
 namespace installer {
 
 class InstallationState;
@@ -28,7 +31,7 @@ class Product;
 // either the Control Panel->Add/Remove Programs list or in the Omaha client
 // state key if running under an MSI installer.
 void AddUninstallShortcutWorkItems(const InstallerState& installer_state,
-                                   const FilePath& setup_path,
+                                   const base::FilePath& setup_path,
                                    const Version& new_version,
                                    const Product& product,
                                    WorkItemList* install_list);
@@ -79,10 +82,10 @@ void AddUsageStatsWorkItems(const InstallationState& original_state,
 // false.
 // |current_version| can be NULL to indicate no Chrome is currently installed.
 bool AppendPostInstallTasks(const InstallerState& installer_state,
-                            const FilePath& setup_path,
+                            const base::FilePath& setup_path,
                             const Version* current_version,
                             const Version& new_version,
-                            const FilePath& temp_path,
+                            const base::FilePath& temp_path,
                             WorkItemList* post_install_task_list);
 
 // Builds the complete WorkItemList used to build the set of installation steps
@@ -99,10 +102,10 @@ bool AppendPostInstallTasks(const InstallerState& installer_state,
 // |current_version| can be NULL to indicate no Chrome is currently installed.
 void AddInstallWorkItems(const InstallationState& original_state,
                          const InstallerState& installer_state,
-                         const FilePath& setup_path,
-                         const FilePath& archive_path,
-                         const FilePath& src_path,
-                         const FilePath& temp_path,
+                         const base::FilePath& setup_path,
+                         const base::FilePath& archive_path,
+                         const base::FilePath& src_path,
+                         const base::FilePath& temp_path,
                          const Version* current_version,
                          const Version& new_version,
                          WorkItemList* install_list);
@@ -116,8 +119,8 @@ void AddInstallWorkItems(const InstallationState& original_state,
 // |may_fail| states whether this is best effort or not. If |may_fail| is true
 // then |work_item_list| will still succeed if the registration fails and
 // no registration rollback will be performed.
-void AddRegisterComDllWorkItems(const FilePath& dll_folder,
-                                const std::vector<FilePath>& dll_files,
+void AddRegisterComDllWorkItems(const base::FilePath& dll_folder,
+                                const std::vector<base::FilePath>& dll_files,
                                 bool system_level,
                                 bool do_register,
                                 bool ignore_failures,
@@ -133,7 +136,7 @@ void AddSetMsiMarkerWorkItem(const InstallerState& installer_state,
 // installation.  This includes handling of the ready-mode option.
 void AddChromeFrameWorkItems(const InstallationState& original_state,
                              const InstallerState& installer_state,
-                             const FilePath& setup_path,
+                             const base::FilePath& setup_path,
                              const Version& new_version,
                              const Product& product,
                              WorkItemList* list);
@@ -143,7 +146,7 @@ void AddChromeFrameWorkItems(const InstallationState& original_state,
 // If |new_version| is empty, the registrations will point to
 // delegate_execute.exe directly in |target_path|.
 void AddDelegateExecuteWorkItems(const InstallerState& installer_state,
-                                 const FilePath& target_path,
+                                 const base::FilePath& target_path,
                                  const Version& new_version,
                                  const Product& product,
                                  WorkItemList* list);
@@ -154,7 +157,7 @@ void AddDelegateExecuteWorkItems(const InstallerState& installer_state,
 // |product|: The product being installed. This method is a no-op if this is
 // anything other than system-level Chrome/Chromium.
 void AddActiveSetupWorkItems(const InstallerState& installer_state,
-                             const FilePath& setup_path,
+                             const base::FilePath& setup_path,
                              const Version& new_version,
                              const Product& product,
                              WorkItemList* list);
@@ -186,7 +189,7 @@ void RefreshElevationPolicy();
 // (and may therefore be empty) when uninstalling.
 void AddQuickEnableChromeFrameWorkItems(const InstallerState& installer_state,
                                         const InstallationState& machine_state,
-                                        const FilePath& setup_path,
+                                        const base::FilePath& setup_path,
                                         const Version& new_version,
                                         WorkItemList* work_item_list);
 
@@ -201,7 +204,7 @@ void AddQuickEnableChromeFrameWorkItems(const InstallerState& installer_state,
 void AddQuickEnableApplicationLauncherWorkItems(
     const InstallerState& installer_state,
     const InstallationState& machine_state,
-    const FilePath& setup_path,
+    const base::FilePath& setup_path,
     const Version& new_version,
     WorkItemList* work_item_list);
 
@@ -210,7 +213,7 @@ void AddQuickEnableApplicationLauncherWorkItems(
 // |installer_state|).  |new_version| is the version of the product(s)
 // currently being installed -- can be empty on uninstall.
 void AddOsUpgradeWorkItems(const InstallerState& installer_state,
-                           const FilePath& setup_path,
+                           const base::FilePath& setup_path,
                            const Version& new_version,
                            const Product& product,
                            WorkItemList* install_list);
@@ -220,7 +223,7 @@ void AddOsUpgradeWorkItems(const InstallerState& installer_state,
 // in |installer_state|).  |new_version| is the version of the product(s)
 // currently being installed -- can be empty on uninstall.
 void AddQueryEULAAcceptanceWorkItems(const InstallerState& installer_state,
-                                     const FilePath& setup_path,
+                                     const base::FilePath& setup_path,
                                      const Version& new_version,
                                      const Product& product,
                                      WorkItemList* work_item_list);
diff --git a/chrome/installer/setup/setup_util.h b/chrome/installer/setup/setup_util.h
index e2e893eac646d4..b2fa9904e806b8 100644
--- a/chrome/installer/setup/setup_util.h
+++ b/chrome/installer/setup/setup_util.h
@@ -16,9 +16,12 @@
 #include "chrome/installer/util/util_constants.h"
 
 class CommandLine;
-class FilePath;
 class Version;
 
+namespace base {
+class FilePath;
+}
+
 namespace installer {
 
 class InstallationState;
@@ -29,15 +32,15 @@ class ProductState;
 // since it checks for courgette header and fails quickly. If that fails
 // tries to apply the patch using regular bsdiff. Returns status code.
 // The installer stage is updated if |installer_state| is non-NULL.
-int ApplyDiffPatch(const FilePath& src,
-                   const FilePath& patch,
-                   const FilePath& dest,
+int ApplyDiffPatch(const base::FilePath& src,
+                   const base::FilePath& patch,
+                   const base::FilePath& dest,
                    const InstallerState* installer_state);
 
 // Find the version of Chrome from an install source directory.
 // Chrome_path should contain at least one version folder.
 // Returns the maximum version found or NULL if no version is found.
-Version* GetMaxVersionFromArchiveDir(const FilePath& chrome_path);
+Version* GetMaxVersionFromArchiveDir(const base::FilePath& chrome_path);
 
 // Spawns a new process that waits for a specified amount of time before
 // attempting to delete |path|.  This is useful for setup to delete the
@@ -46,7 +49,7 @@ Version* GetMaxVersionFromArchiveDir(const FilePath& chrome_path);
 // Returns true if a new process was started, false otherwise.  Note that
 // given the nature of this function, it is not possible to know if the
 // delete operation itself succeeded.
-bool DeleteFileFromTempProcess(const FilePath& path,
+bool DeleteFileFromTempProcess(const base::FilePath& path,
                                uint32 delay_before_delete_ms);
 
 // Returns true and populates |setup_exe| with the path to an existing product
@@ -55,17 +58,17 @@ bool DeleteFileFromTempProcess(const FilePath& path,
 bool GetExistingHigherInstaller(const InstallationState& original_state,
                                 bool system_install,
                                 const Version& installer_version,
-                                FilePath* setup_exe);
+                                base::FilePath* setup_exe);
 
 // Invokes the pre-existing |setup_exe| to handle the current operation (as
 // dictated by |command_line|). An installerdata file, if specified, is first
 // unconditionally copied into place so that it will be in effect in case the
 // invoked |setup_exe| runs the newly installed product prior to exiting.
 // Returns true if |setup_exe| was launched, false otherwise.
-bool DeferToExistingInstall(const FilePath& setup_exe,
+bool DeferToExistingInstall(const base::FilePath& setup_exe,
                             const CommandLine& command_line,
                             const InstallerState& installer_state,
-                            const FilePath& temp_path,
+                            const base::FilePath& temp_path,
                             InstallStatus* install_status);
 
 // This class will enable the privilege defined by |privilege_name| on the
diff --git a/chrome/installer/setup/uninstall.h b/chrome/installer/setup/uninstall.h
index 206bd35f2a2a69..f76005b0d454d1 100644
--- a/chrome/installer/setup/uninstall.h
+++ b/chrome/installer/setup/uninstall.h
@@ -14,7 +14,10 @@
 
 class BrowserDistribution;
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
@@ -54,7 +57,7 @@ void RemoveChromeLegacyRegistryKeys(BrowserDistribution* dist,
 installer::InstallStatus UninstallProduct(
     const InstallationState& original_state,
     const InstallerState& installer_state,
-    const FilePath& setup_path,
+    const base::FilePath& setup_path,
     const Product& dist,
     bool remove_all,
     bool force_uninstall,
diff --git a/chrome/installer/test/alternate_version_generator.h b/chrome/installer/test/alternate_version_generator.h
index 0ae0d5c3725928..fe60a6a86b6726 100644
--- a/chrome/installer/test/alternate_version_generator.h
+++ b/chrome/installer/test/alternate_version_generator.h
@@ -9,9 +9,12 @@
 
 #include <string>
 
-class FilePath;
 class Version;
 
+namespace base {
+class FilePath;
+}
+
 namespace upgrade_test {
 
 enum Direction {
@@ -25,8 +28,8 @@ enum Direction {
 // |target_path| is clobbered.  Returns true on success.  |original_version| and
 // |new_version|, when non-NULL, are given the original and new version numbers
 // on success.
-bool GenerateAlternateVersion(const FilePath& original_installer_path,
-                              const FilePath& target_path,
+bool GenerateAlternateVersion(const base::FilePath& original_installer_path,
+                              const base::FilePath& target_path,
                               Direction direction,
                               std::wstring* original_version,
                               std::wstring* new_version);
@@ -35,16 +38,16 @@ bool GenerateAlternateVersion(const FilePath& original_installer_path,
 // |target_file|, modifying the version of the copy according to |direction|.
 // Any previous file at |target_file| is clobbered. Returns true on success.
 // Note that |target_file| may still be mutated on failure.
-bool GenerateAlternatePEFileVersion(const FilePath& original_file,
-                                    const FilePath& target_file,
+bool GenerateAlternatePEFileVersion(const base::FilePath& original_file,
+                                    const base::FilePath& target_file,
                                     Direction direction);
 
 // Given a path to a PEImage in |original_file|, copy that file to
 // |target_file|, modifying the version of the copy according to |version|.
 // Any previous file at |target_file| is clobbered. Returns true on success.
 // Note that |target_file| may still be mutated on failure.
-bool GenerateSpecificPEFileVersion(const FilePath& original_file,
-                                   const FilePath& target_file,
+bool GenerateSpecificPEFileVersion(const base::FilePath& original_file,
+                                   const base::FilePath& target_file,
                                    const Version& version);
 
 }  // namespace upgrade_test
diff --git a/chrome/installer/test/resource_loader.h b/chrome/installer/test/resource_loader.h
index 026e21cfebdeac..b43056c4289952 100644
--- a/chrome/installer/test/resource_loader.h
+++ b/chrome/installer/test/resource_loader.h
@@ -14,7 +14,9 @@
 
 #include "base/basictypes.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace upgrade_test {
 
@@ -25,7 +27,7 @@ class ResourceLoader {
   ~ResourceLoader();
 
   // Loads |pe_image_path| in preparation for loading its resources.
-  bool Initialize(const FilePath& pe_image_path);
+  bool Initialize(const base::FilePath& pe_image_path);
 
   // Places the address and size of the resource |name| of |type| into
   // |resource_data|, returning true on success.  The address of the resource is
diff --git a/chrome/installer/test/resource_updater.h b/chrome/installer/test/resource_updater.h
index dbbca9fafc5d84..6d6bb9fb5fb022 100644
--- a/chrome/installer/test/resource_updater.h
+++ b/chrome/installer/test/resource_updater.h
@@ -14,7 +14,9 @@
 
 #include "base/basictypes.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace upgrade_test {
 
@@ -25,12 +27,12 @@ class ResourceUpdater {
   ~ResourceUpdater();
 
   // Loads |pe_image_path| in preparation for updating its resources.
-  bool Initialize(const FilePath& pe_image_path);
+  bool Initialize(const base::FilePath& pe_image_path);
 
   // Replaces the contents of the resource |name| of |type| and |language_id|
   // with the contents of |input_file|, returning true on success.
   bool Update(const std::wstring& name, const std::wstring& type,
-              WORD language_id, const FilePath& input_file);
+              WORD language_id, const base::FilePath& input_file);
 
   // Commits all updates to the file on disk.
   bool Commit();
diff --git a/chrome/installer/util/auto_launch_util.h b/chrome/installer/util/auto_launch_util.h
index 862ebd077b15e6..2f2b650ff85826 100644
--- a/chrome/installer/util/auto_launch_util.h
+++ b/chrome/installer/util/auto_launch_util.h
@@ -7,7 +7,9 @@
 
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 // A namespace containing the platform specific implementation of setting Chrome
 // to launch at user login.
@@ -32,7 +34,7 @@ namespace auto_launch_util {
 // (as it will default to the application path of the current executable).
 bool AutoStartRequested(const string16& profile_directory,
                         bool window_requested,
-                        const FilePath& application_path);
+                        const base::FilePath& application_path);
 
 // Disables all auto-start features. |profile_directory| is the name of the
 // directory (leaf, not the full path) that contains the profile that was set
@@ -47,7 +49,7 @@ void DisableAllAutoStartFeatures(const string16& profile_directory);
 // auto-launch, ie. the installer. This is because |application_path|, if left
 // blank, defaults to the application path of the current executable.
 void EnableForegroundStartAtLogin(const string16& profile_directory,
-                                  const FilePath& application_path);
+                                  const base::FilePath& application_path);
 
 // Disables auto-starting Chrome in foreground mode at user login.
 // |profile_directory| is the name of the directory (leaf, not the full path)
diff --git a/chrome/installer/util/duplicate_tree_detector.h b/chrome/installer/util/duplicate_tree_detector.h
index 1ae26f06169ee6..052826031db45c 100644
--- a/chrome/installer/util/duplicate_tree_detector.h
+++ b/chrome/installer/util/duplicate_tree_detector.h
@@ -9,7 +9,9 @@
 #ifndef CHROME_INSTALLER_UTIL_DUPLICATE_TREE_DETECTOR_H_
 #define CHROME_INSTALLER_UTIL_DUPLICATE_TREE_DETECTOR_H_
 
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
@@ -19,8 +21,8 @@ namespace installer {
 // Note that THIS IS A WEAK DEFINITION OF IDENTICAL and is intended only to
 // catch cases of missing files or obvious modifications.
 // It notably DOES NOT CHECKSUM the files.
-bool IsIdenticalFileHierarchy(const FilePath& src_path,
-                              const FilePath& dest_path);
+bool IsIdenticalFileHierarchy(const base::FilePath& src_path,
+                              const base::FilePath& dest_path);
 
 }  // namespace installer
 
diff --git a/chrome/installer/util/google_chrome_distribution.h b/chrome/installer/util/google_chrome_distribution.h
index 0a315bd9794a94..32bacd06250613 100644
--- a/chrome/installer/util/google_chrome_distribution.h
+++ b/chrome/installer/util/google_chrome_distribution.h
@@ -13,10 +13,9 @@
 #include "chrome/installer/util/browser_distribution.h"
 #include "chrome/installer/util/util_constants.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 class GoogleChromeDistribution : public BrowserDistribution {
@@ -32,7 +31,7 @@ class GoogleChromeDistribution : public BrowserDistribution {
   //   the user has opted in to providing anonymous usage data.
   virtual void DoPostUninstallOperations(
       const Version& version,
-      const FilePath& local_data_path,
+      const base::FilePath& local_data_path,
       const string16& distribution_data) OVERRIDE;
 
   virtual string16 GetActiveSetupGuid() OVERRIDE;
@@ -92,7 +91,7 @@ class GoogleChromeDistribution : public BrowserDistribution {
                                     int flavor) OVERRIDE;
 
   virtual void LaunchUserExperiment(
-      const FilePath& setup_path,
+      const base::FilePath& setup_path,
       installer::InstallStatus status,
       const Version& version,
       const installer::Product& product,
@@ -105,7 +104,7 @@ class GoogleChromeDistribution : public BrowserDistribution {
       int flavor,
       const string16& experiment_group,
       const installer::Product& installation,
-      const FilePath& application_path) OVERRIDE;
+      const base::FilePath& application_path) OVERRIDE;
 
   virtual bool ShouldSetExperimentLabels() OVERRIDE;
 
@@ -128,7 +127,7 @@ class GoogleChromeDistribution : public BrowserDistribution {
   // Returns true if uninstall_metrics has been successfully populated with
   // the uninstall metrics, false otherwise.
   virtual bool ExtractUninstallMetricsFromFile(
-      const FilePath& file_path, string16* uninstall_metrics);
+      const base::FilePath& file_path, string16* uninstall_metrics);
 
   // Extracts uninstall metrics from the given JSON value.
   virtual bool ExtractUninstallMetrics(const base::DictionaryValue& root,
diff --git a/chrome/installer/util/helper.h b/chrome/installer/util/helper.h
index e588be1463e8e0..68d873cbcf10eb 100644
--- a/chrome/installer/util/helper.h
+++ b/chrome/installer/util/helper.h
@@ -11,7 +11,10 @@
 #include <vector>
 
 class BrowserDistribution;
+
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
@@ -20,7 +23,7 @@ namespace installer {
 // system_install: if true, the function returns system wide location
 //                 (ProgramFiles\Google). Otherwise it returns user specific
 //                 location (Document And Settings\<user>\Local Settings...)
-FilePath GetChromeInstallPath(bool system_install, BrowserDistribution* dist);
+base::FilePath GetChromeInstallPath(bool system_install, BrowserDistribution* dist);
 
 // Returns the path(s) to the directory that holds the user data (primary and,
 // if applicable to |dist|, alternate).  This is always inside a user's local
@@ -31,7 +34,7 @@ FilePath GetChromeInstallPath(bool system_install, BrowserDistribution* dist);
 // otherwise. If more than one path is returned, they are guaranteed to be
 // siblings.
 void GetChromeUserDataPaths(BrowserDistribution* dist,
-                            std::vector<FilePath>* paths);
+                            std::vector<base::FilePath>* paths);
 
 // Returns the distribution corresponding to the current process's binaries.
 // In the case of a multi-install product, this will be the CHROME_BINARIES
diff --git a/chrome/installer/util/installation_validator.h b/chrome/installer/util/installation_validator.h
index 6315a74e76b3ea..dfc7c3e44802a7 100644
--- a/chrome/installer/util/installation_validator.h
+++ b/chrome/installer/util/installation_validator.h
@@ -15,7 +15,10 @@
 #include "chrome/installer/util/browser_distribution.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
@@ -214,7 +217,7 @@ class InstallationValidator {
                                const ProductState& binaries_state,
                                bool* is_valid);
   static void ValidateSetupPath(const ProductContext& ctx,
-                                const FilePath& setup_exe,
+                                const base::FilePath& setup_exe,
                                 const char* purpose,
                                 bool* is_valid);
   static void ValidateCommandExpectations(const ProductContext& ctx,
diff --git a/chrome/installer/util/installer_util_test_common.h b/chrome/installer/util/installer_util_test_common.h
index 8839f6d030eacd..0a4096879132fa 100644
--- a/chrome/installer/util/installer_util_test_common.h
+++ b/chrome/installer/util/installer_util_test_common.h
@@ -5,7 +5,9 @@
 #ifndef CHROME_INSTALLER_UTIL_INSTALLER_UTIL_TEST_COMMON_H_
 #define CHROME_INSTALLER_UTIL_INSTALLER_UTIL_TEST_COMMON_H_
 
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
@@ -13,7 +15,7 @@ namespace test {
 
 // Copies the hierarcy in |from| to |to|.
 // Keeps all file properties identical (creation time, etc.).
-bool CopyFileHierarchy(const FilePath& from, const FilePath& to);
+bool CopyFileHierarchy(const base::FilePath& from, const base::FilePath& to);
 
 }  // namespace test
 
diff --git a/chrome/installer/util/logging_installer.h b/chrome/installer/util/logging_installer.h
index c7ccb4650cf108..42153ba4b83cc8 100644
--- a/chrome/installer/util/logging_installer.h
+++ b/chrome/installer/util/logging_installer.h
@@ -7,14 +7,14 @@
 
 #include "base/basictypes.h"
 
-namespace installer {
-  class MasterPreferences;
-}
-
+namespace base {
 class FilePath;
+}
 
 namespace installer {
 
+class MasterPreferences;
+
 // Verbose installer runs clock in at around 50K, non-verbose much less than
 // that. Some installer operations span multiple setup.exe runs, so we try
 // to keep enough for at least 10 runs or so at any given time.
@@ -41,7 +41,7 @@ enum TruncateResult {
 // If the file needed truncation, but the truncation failed, the file will be
 // deleted and the function returns LOGFILE_DELETED. This is done to prevent
 // run-away log files and guard against full disks.
-TruncateResult TruncateLogFileIfNeeded(const FilePath& log_file);
+TruncateResult TruncateLogFileIfNeeded(const base::FilePath& log_file);
 
 // Call to initialize logging for Chrome installer.
 void InitInstallerLogging(const installer::MasterPreferences& prefs);
@@ -50,7 +50,7 @@ void InitInstallerLogging(const installer::MasterPreferences& prefs);
 void EndInstallerLogging();
 
 // Returns the full path of the log file.
-FilePath GetLogFilePath(const installer::MasterPreferences& prefs);
+base::FilePath GetLogFilePath(const installer::MasterPreferences& prefs);
 
 }  // namespace installer
 
diff --git a/chrome/installer/util/lzma_util.h b/chrome/installer/util/lzma_util.h
index 09a8643a4166e2..634309cb058485 100644
--- a/chrome/installer/util/lzma_util.h
+++ b/chrome/installer/util/lzma_util.h
@@ -12,7 +12,9 @@
 
 #include "base/basictypes.h"
 
+namespace base {
 class FilePath;
+}
 
 // This is a utility class that acts as a wrapper around LZMA SDK library
 class LzmaUtil {
@@ -40,7 +42,7 @@ class LzmaUtil {
   void CloseArchive();
 
  protected:
-  bool CreateDirectory(const FilePath& dir);
+  bool CreateDirectory(const base::FilePath& dir);
 
  private:
   HANDLE archive_handle_;
diff --git a/chrome/installer/util/master_preferences.h b/chrome/installer/util/master_preferences.h
index 46dc7c97b34ad4..773d6031e25fa2 100644
--- a/chrome/installer/util/master_preferences.h
+++ b/chrome/installer/util/master_preferences.h
@@ -15,10 +15,9 @@
 #include "base/memory/scoped_ptr.h"
 #include "googleurl/src/gurl.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace installer {
@@ -91,7 +90,7 @@ class MasterPreferences {
 
   // Parses a specific preferences file and does not merge any command line
   // switches with the distribution dictionary.
-  explicit MasterPreferences(const FilePath& prefs_path);
+  explicit MasterPreferences(const base::FilePath& prefs_path);
 
   // Parses a preferences directly from |prefs| and does not merge any command
   // line switches with the distribution dictionary.
diff --git a/chrome/installer/util/master_preferences_dummy.cc b/chrome/installer/util/master_preferences_dummy.cc
index 75377f5a4c1e43..610d7d36f1c39f 100644
--- a/chrome/installer/util/master_preferences_dummy.cc
+++ b/chrome/installer/util/master_preferences_dummy.cc
@@ -22,7 +22,7 @@ MasterPreferences::MasterPreferences(const CommandLine& cmd_line)
     : distribution_(NULL), preferences_read_from_file_(false) {
 }
 
-MasterPreferences::MasterPreferences(const FilePath& prefs_path)
+MasterPreferences::MasterPreferences(const base::FilePath& prefs_path)
     : distribution_(NULL), preferences_read_from_file_(false) {
 }
 
diff --git a/chrome/installer/util/work_item.h b/chrome/installer/util/work_item.h
index d7b3ae76b28d70..30118609f6a48c 100644
--- a/chrome/installer/util/work_item.h
+++ b/chrome/installer/util/work_item.h
@@ -25,12 +25,15 @@ class CreateRegKeyWorkItem;
 class DeleteTreeWorkItem;
 class DeleteRegKeyWorkItem;
 class DeleteRegValueWorkItem;
-class FilePath;
 class MoveTreeWorkItem;
 class SelfRegWorkItem;
 class SetRegValueWorkItem;
 class WorkItemList;
 
+namespace base {
+class FilePath;
+}
+
 // A base class that defines APIs to perform/rollback an action or a
 // sequence of actions during install/update/uninstall.
 class WorkItem {
@@ -78,14 +81,14 @@ class WorkItem {
   // * If overwrite_option is NEW_NAME_IF_IN_USE, file is copied with an
   //   alternate name specified by alternative_path.
   static CopyTreeWorkItem* CreateCopyTreeWorkItem(
-      const FilePath& source_path,
-      const FilePath& dest_path,
-      const FilePath& temp_dir,
+      const base::FilePath& source_path,
+      const base::FilePath& dest_path,
+      const base::FilePath& temp_dir,
       CopyOverWriteOption overwrite_option,
-      const FilePath& alternative_path);
+      const base::FilePath& alternative_path);
 
   // Create a CreateDirWorkItem that creates a directory at the given path.
-  static CreateDirWorkItem* CreateCreateDirWorkItem(const FilePath& path);
+  static CreateDirWorkItem* CreateCreateDirWorkItem(const base::FilePath& path);
 
   // Create a CreateRegKeyWorkItem that creates a registry key at the given
   // path.
@@ -107,16 +110,16 @@ class WorkItem {
   // hierarchy at the given root path. A key file can be optionally specified
   // by key_path.
   static DeleteTreeWorkItem* CreateDeleteTreeWorkItem(
-      const FilePath& root_path,
-      const FilePath& temp_path,
-      const std::vector<FilePath>& key_paths);
+      const base::FilePath& root_path,
+      const base::FilePath& temp_path,
+      const std::vector<base::FilePath>& key_paths);
 
   // Create a MoveTreeWorkItem that recursively moves a file system hierarchy
   // from source path to destination path.
   static MoveTreeWorkItem* CreateMoveTreeWorkItem(
-      const FilePath& source_path,
-      const FilePath& dest_path,
-      const FilePath& temp_dir,
+      const base::FilePath& source_path,
+      const base::FilePath& dest_path,
+      const base::FilePath& temp_dir,
       MoveTreeOption duplicate_option);
 
   // Create a SetRegValueWorkItem that sets a registry value with REG_SZ type
diff --git a/chrome/installer/util/work_item_list.h b/chrome/installer/util/work_item_list.h
index f350f39160b400..29a458742e3fc1 100644
--- a/chrome/installer/util/work_item_list.h
+++ b/chrome/installer/util/work_item_list.h
@@ -15,7 +15,9 @@
 #include "base/memory/scoped_ptr.h"
 #include "chrome/installer/util/work_item.h"
 
+namespace base {
 class FilePath;
+}
 
 // A WorkItem subclass that recursively contains a list of WorkItems. Thus it
 // provides functionalities to carry out or roll back the sequence of actions
@@ -58,7 +60,7 @@ class WorkItemList : public WorkItem {
       const std::wstring& alternative_path = L"");
 
   // Add a CreateDirWorkItem that creates a directory at the given path.
-  virtual WorkItem* AddCreateDirWorkItem(const FilePath& path);
+  virtual WorkItem* AddCreateDirWorkItem(const base::FilePath& path);
 
   // Add a CreateRegKeyWorkItem that creates a registry key at the given
   // path.
@@ -80,13 +82,13 @@ class WorkItemList : public WorkItem {
   // hierarchy at the given root path. A key file can be optionally specified
   // by key_path.
   virtual WorkItem* AddDeleteTreeWorkItem(
-      const FilePath& root_path,
-      const FilePath& temp_path,
-      const std::vector<FilePath>& key_paths);
+      const base::FilePath& root_path,
+      const base::FilePath& temp_path,
+      const std::vector<base::FilePath>& key_paths);
 
   // Same as above but without support for key files.
-  virtual WorkItem* AddDeleteTreeWorkItem(const FilePath& root_path,
-                                          const FilePath& temp_path);
+  virtual WorkItem* AddDeleteTreeWorkItem(const base::FilePath& root_path,
+                                          const base::FilePath& temp_path);
 
   // Add a MoveTreeWorkItem to the list of work items.
   virtual WorkItem* AddMoveTreeWorkItem(const std::wstring& source_path,
diff --git a/chrome/renderer/chrome_content_renderer_client.h b/chrome/renderer/chrome_content_renderer_client.h
index 1c805af5f07307..ba9f3dc2367aae 100644
--- a/chrome/renderer/chrome_content_renderer_client.h
+++ b/chrome/renderer/chrome_content_renderer_client.h
@@ -66,7 +66,7 @@ class ChromeContentRendererClient : public content::ContentRendererClient {
       WebKit::WebPlugin** plugin) OVERRIDE;
   virtual WebKit::WebPlugin* CreatePluginReplacement(
       content::RenderView* render_view,
-      const FilePath& plugin_path) OVERRIDE;
+      const base::FilePath& plugin_path) OVERRIDE;
   virtual bool HasErrorPage(int http_status_code,
                             std::string* error_domain) OVERRIDE;
   virtual void GetNavigationErrorStrings(
diff --git a/chrome/renderer/mock_printer.h b/chrome/renderer/mock_printer.h
index 625c140ed2f93c..5f494750bcc9e4 100644
--- a/chrome/renderer/mock_printer.h
+++ b/chrome/renderer/mock_printer.h
@@ -99,8 +99,8 @@ class MockPrinter {
   bool GetBitmapChecksum(unsigned int page, std::string* checksum) const;
   bool GetSource(unsigned int page, const void** data, uint32* size) const;
   bool GetBitmap(unsigned int page, const void** data, uint32* size) const;
-  bool SaveSource(unsigned int page, const FilePath& filepath) const;
-  bool SaveBitmap(unsigned int page, const FilePath& filepath) const;
+  bool SaveSource(unsigned int page, const base::FilePath& filepath) const;
+  bool SaveBitmap(unsigned int page, const base::FilePath& filepath) const;
 
  protected:
   int CreateDocumentCookie();
diff --git a/chrome/service/cloud_print/print_system.h b/chrome/service/cloud_print/print_system.h
index 5e73640a080455..cf6246662ad519 100644
--- a/chrome/service/cloud_print/print_system.h
+++ b/chrome/service/cloud_print/print_system.h
@@ -11,13 +11,11 @@
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
-
 #include "printing/backend/print_backend.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 namespace printing {
@@ -131,7 +129,7 @@ class PrintSystem : public base::RefCountedThreadSafe<PrintSystem> {
     // time. Subsequent calls to Spool (before the Delegate::OnJobSpoolSucceeded
     // or Delegate::OnJobSpoolFailed methods are called) can fail.
     virtual bool Spool(const std::string& print_ticket,
-                       const FilePath& print_data_file_path,
+                       const base::FilePath& print_data_file_path,
                        const std::string& print_data_mime_type,
                        const std::string& printer_name,
                        const std::string& job_title,
diff --git a/chrome/test/automation/automation_json_requests.h b/chrome/test/automation/automation_json_requests.h
index 860fa61b512f3a..6f1fb45a83b455 100644
--- a/chrome/test/automation/automation_json_requests.h
+++ b/chrome/test/automation/automation_json_requests.h
@@ -16,10 +16,10 @@
 #include "ui/base/keycodes/keyboard_codes.h"
 
 class AutomationMessageSender;
-class FilePath;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 class ListValue;
 class Value;
 }
@@ -244,7 +244,7 @@ bool SendReloadJSONRequest(
 bool SendCaptureEntirePageJSONRequest(
     AutomationMessageSender* sender,
     const WebViewLocator& locator,
-    const FilePath& path,
+    const base::FilePath& path,
     automation::Error* error) WARN_UNUSED_RESULT;
 
 #if !defined(NO_TCMALLOC) && (defined(OS_LINUX) || defined(OS_CHROMEOS))
@@ -410,7 +410,7 @@ bool SendDragAndDropFilePathsJSONRequest(
     const WebViewLocator& locator,
     int x,
     int y,
-    const std::vector<FilePath::StringType>& paths,
+    const std::vector<base::FilePath::StringType>& paths,
     automation::Error* error) WARN_UNUSED_RESULT;
 
 // Requests to set the given view's bounds. Returns true on success.
@@ -466,7 +466,7 @@ bool SendGetChromeDriverAutomationVersion(
 // the extension will be installed silently. Returns true on success.
 bool SendInstallExtensionJSONRequest(
     AutomationMessageSender* sender,
-    const FilePath& path,
+    const base::FilePath& path,
     bool with_ui,
     std::string* extension_id,
     automation::Error* error) WARN_UNUSED_RESULT;
diff --git a/chrome/test/automation/tab_proxy.h b/chrome/test/automation/tab_proxy.h
index 2c417e9870ec9e..22942dc33a974a 100644
--- a/chrome/test/automation/tab_proxy.h
+++ b/chrome/test/automation/tab_proxy.h
@@ -27,13 +27,14 @@
 #include "ui/base/window_open_disposition.h"
 
 class BrowserProxy;
-class FilePath;
 class GURL;
+
 namespace IPC {
 class Message;
 }
 
 namespace base {
+class FilePath;
 class Value;
 }
 
@@ -203,7 +204,7 @@ class TabProxy : public AutomationResourceProxy {
 
   // Captures the entire page and saves as a PNG at the given path. Returns
   // true on success.
-  bool CaptureEntirePageAsPNG(const FilePath& path) WARN_UNUSED_RESULT;
+  bool CaptureEntirePageAsPNG(const base::FilePath& path) WARN_UNUSED_RESULT;
 
 #if defined(OS_WIN)
   // Resizes the tab window.
diff --git a/chrome/test/base/ui_test_utils.h b/chrome/test/base/ui_test_utils.h
index 603419cc049ce8..fd5cc186ff9cf9 100644
--- a/chrome/test/base/ui_test_utils.h
+++ b/chrome/test/base/ui_test_utils.h
@@ -29,12 +29,15 @@
 class AppModalDialog;
 class BookmarkModel;
 class Browser;
-class FilePath;
 class LocationBar;
 class Profile;
 class SkBitmap;
 class TemplateURLService;
 
+namespace base {
+class FilePath;
+}
+
 namespace chrome {
 struct NavigateParams;
 }
@@ -107,17 +110,18 @@ void NavigateToURLBlockUntilNavigationsComplete(Browser* browser,
 // Generate the file path for testing a particular test.
 // The file for the tests is all located in
 // test_root_directory/dir/<file>
-// The returned path is FilePath format.
-FilePath GetTestFilePath(const FilePath& dir, const FilePath& file);
+// The returned path is base::FilePath format.
+base::FilePath GetTestFilePath(const base::FilePath& dir,
+                               const base::FilePath& file);
 
 // Generate the URL for testing a particular test.
 // HTML for the tests is all located in
 // test_root_directory/dir/<file>
 // The returned path is GURL format.
-GURL GetTestUrl(const FilePath& dir, const FilePath& file);
+GURL GetTestUrl(const base::FilePath& dir, const base::FilePath& file);
 
 // Generate the path of the build directory, relative to the source root.
-bool GetRelativeBuildDirectory(FilePath* build_dir);
+bool GetRelativeBuildDirectory(base::FilePath* build_dir);
 
 // Blocks until an application modal dialog is showns and returns it.
 AppModalDialog* WaitForAppModalDialog();
@@ -275,12 +279,12 @@ bool TakeEntirePageSnapshot(content::RenderViewHost* rvh,
 // Saves a snapshot of the entire screen to a file named
 // ChromiumSnapshotYYYYMMDDHHMMSS.png to |directory|, returning true on success.
 // The path to the file produced is returned in |screenshot_path| if non-NULL.
-bool SaveScreenSnapshotToDirectory(const FilePath& directory,
-                                   FilePath* screenshot_path);
+bool SaveScreenSnapshotToDirectory(const base::FilePath& directory,
+                                   base::FilePath* screenshot_path);
 
 // Saves a snapshot of the entire screen as above to the current user's desktop.
 // The Chrome path provider must be registered prior to calling this function.
-bool SaveScreenSnapshotToDesktop(FilePath* screenshot_path);
+bool SaveScreenSnapshotToDesktop(base::FilePath* screenshot_path);
 #endif
 
 // Configures the geolocation provider to always return the given position.
diff --git a/chrome/test/chromedriver/chrome_finder.h b/chrome/test/chromedriver/chrome_finder.h
index e9df71e306cff6..0e7ca90fb4549a 100644
--- a/chrome/test/chromedriver/chrome_finder.h
+++ b/chrome/test/chromedriver/chrome_finder.h
@@ -9,18 +9,20 @@
 
 #include "base/callback_forward.h"
 
+namespace base {
 class FilePath;
+}
 
 // Gets the path to the default Chrome executable. Returns true on success.
-bool FindChrome(FilePath* browser_exe);
+bool FindChrome(base::FilePath* browser_exe);
 
 namespace internal {
 
 bool FindExe(
-    const base::Callback<bool(const FilePath&)>& exists_func,
-    const std::vector<FilePath>& rel_paths,
-    const std::vector<FilePath>& locations,
-    FilePath* out_path);
+    const base::Callback<bool(const base::FilePath&)>& exists_func,
+    const std::vector<base::FilePath>& rel_paths,
+    const std::vector<base::FilePath>& locations,
+    base::FilePath* out_path);
 
 }  // namespace internal
 
diff --git a/chrome/test/chromedriver/chrome_launcher.h b/chrome/test/chromedriver/chrome_launcher.h
index a0caa1ac024ff0..3763d2c823a4b3 100644
--- a/chrome/test/chromedriver/chrome_launcher.h
+++ b/chrome/test/chromedriver/chrome_launcher.h
@@ -8,9 +8,12 @@
 #include "base/memory/scoped_ptr.h"
 
 class Chrome;
-class FilePath;
 class Status;
 
+namespace base {
+class FilePath;
+}
+
 // Launches Chrome. Must be thread safe.
 class ChromeLauncher {
  public:
@@ -18,7 +21,7 @@ class ChromeLauncher {
 
   // Launches Chrome found at the given path. If the path
   // is empty, the default Chrome binary is to be used.
-  virtual Status Launch(const FilePath& chrome_exe,
+  virtual Status Launch(const base::FilePath& chrome_exe,
                         scoped_ptr<Chrome>* chrome) = 0;
 };
 
diff --git a/chrome/test/chromedriver/chrome_launcher_impl.h b/chrome/test/chromedriver/chrome_launcher_impl.h
index 1910ac5dceaa0e..f8a4cf656485a5 100644
--- a/chrome/test/chromedriver/chrome_launcher_impl.h
+++ b/chrome/test/chromedriver/chrome_launcher_impl.h
@@ -13,10 +13,13 @@
 #include "chrome/test/chromedriver/net/sync_websocket_factory.h"
 
 class Chrome;
-class FilePath;
 class Status;
 class URLRequestContextGetter;
 
+namespace base {
+class FilePath;
+}
+
 class ChromeLauncherImpl : public ChromeLauncher {
  public:
   explicit ChromeLauncherImpl(URLRequestContextGetter* context_getter,
@@ -24,7 +27,7 @@ class ChromeLauncherImpl : public ChromeLauncher {
   virtual ~ChromeLauncherImpl();
 
   // Overridden from ChromeLauncher:
-  virtual Status Launch(const FilePath& chrome_exe,
+  virtual Status Launch(const base::FilePath& chrome_exe,
                         scoped_ptr<Chrome>* chrome) OVERRIDE;
 
  private:
diff --git a/chrome/test/logging/win/file_logger.h b/chrome/test/logging/win/file_logger.h
index d09b68235b4f3c..5a6caa6da7a0fc 100644
--- a/chrome/test/logging/win/file_logger.h
+++ b/chrome/test/logging/win/file_logger.h
@@ -11,7 +11,9 @@
 #include "base/string16.h"
 #include "base/win/event_trace_controller.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace logging_win {
 
@@ -59,7 +61,7 @@ class FileLogger {
   // extension for such files is .etl.  Returns false if the session could not
   // be started (e.g., if not running as admin) or if no providers could be
   // enabled.
-  bool StartLogging(const FilePath& log_file);
+  bool StartLogging(const base::FilePath& log_file);
 
   // Stops capturing logs.
   void StopLogging();
diff --git a/chrome/test/logging/win/log_file_printer.cc b/chrome/test/logging/win/log_file_printer.cc
index 1d5dfd24f5f44d..162c1e36d4ead1 100644
--- a/chrome/test/logging/win/log_file_printer.cc
+++ b/chrome/test/logging/win/log_file_printer.cc
@@ -242,7 +242,7 @@ void EventPrinter::OnTraceEvent(const EVENT_TRACE* event,
 
 }  // namespace
 
-void logging_win::PrintLogFile(const FilePath& log_file,
+void logging_win::PrintLogFile(const base::FilePath& log_file,
                                std::ostream* out) {
   EventPrinter printer(out);
   logging_win::ReadLogFile(log_file, &printer);
diff --git a/chrome/test/logging/win/log_file_printer.h b/chrome/test/logging/win/log_file_printer.h
index 85a54e97340dff..d9953f1dcaa926 100644
--- a/chrome/test/logging/win/log_file_printer.h
+++ b/chrome/test/logging/win/log_file_printer.h
@@ -11,14 +11,16 @@
 
 #include <iosfwd>
 
+namespace base {
 class FilePath;
+}
 
 namespace logging_win {
 
 // Reads |log_file|, emitting messages to |out|.  Although it is safe to call
 // this from multiple threads, only one file may be read at a time; other
 // threads trying to read other log files will be blocked waiting.
-void PrintLogFile(const FilePath& log_file, std::ostream* out);
+void PrintLogFile(const base::FilePath& log_file, std::ostream* out);
 
 }  // namespace logging_win
 
diff --git a/chrome/test/logging/win/log_file_reader.h b/chrome/test/logging/win/log_file_reader.h
index 762a840cdbf3c0..aca4b0acea46fa 100644
--- a/chrome/test/logging/win/log_file_reader.h
+++ b/chrome/test/logging/win/log_file_reader.h
@@ -17,7 +17,9 @@
 #include "base/logging.h"
 #include "base/string_piece.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace logging_win {
 
@@ -69,7 +71,7 @@ class LogFileDelegate {
 // parsed.  Although it is safe to call this from multiple threads, only one
 // file may be read at a time; other threads trying to read other log files will
 // be blocked waiting.
-void ReadLogFile(const FilePath& log_file, LogFileDelegate* delegate);
+void ReadLogFile(const base::FilePath& log_file, LogFileDelegate* delegate);
 
 }  // namespace logging_win
 
diff --git a/chrome/test/ui/ui_test.h b/chrome/test/ui/ui_test.h
index 98c75fe0478528..ade8dfb4170695 100644
--- a/chrome/test/ui/ui_test.h
+++ b/chrome/test/ui/ui_test.h
@@ -30,12 +30,12 @@
 
 class AutomationProxy;
 class BrowserProxy;
-class FilePath;
 class GURL;
 class TabProxy;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 }
 
 // Base class for UI Tests. This implements the core of the functions.
@@ -146,15 +146,15 @@ class UITestBase {
   bool CloseBrowser(BrowserProxy* browser, bool* application_closed) const;
 
   // Gets the executable file path of the Chrome browser process.
-  const FilePath::CharType* GetExecutablePath();
+  const base::FilePath::CharType* GetExecutablePath();
 
   // Returns the directory name where the "typical" user data is that we use
   // for testing.
-  static FilePath ComputeTypicalUserDataSource(ProfileType profile_type);
+  static base::FilePath ComputeTypicalUserDataSource(ProfileType profile_type);
 
   // Return the user data directory being used by the browser instance in
   // UITest::SetUp().
-  FilePath user_data_dir() const {
+  base::FilePath user_data_dir() const {
     return launcher_->user_data_dir();
   }
 
@@ -163,8 +163,8 @@ class UITestBase {
   // copied into the user data directory for the test and the files will be
   // evicted from the OS cache. To start with a blank profile, supply an empty
   // string (the default).
-  const FilePath& template_user_data() const { return template_user_data_; }
-  void set_template_user_data(const FilePath& template_user_data) {
+  const base::FilePath& template_user_data() const { return template_user_data_; }
+  void set_template_user_data(const base::FilePath& template_user_data) {
     template_user_data_ = template_user_data;
   }
 
@@ -226,7 +226,7 @@ class UITestBase {
   std::string CheckErrorsAndCrashes() const;
 
   // Use Chromium binaries from the given directory.
-  void SetBrowserDirectory(const FilePath& dir);
+  void SetBrowserDirectory(const base::FilePath& dir);
 
   // Appends a command-line switch (no associated value) to be passed to the
   // browser when launched.
@@ -283,10 +283,10 @@ class UITestBase {
   // ********* Member variables *********
 
   // Path to the browser executable.
-  FilePath browser_directory_;
+  base::FilePath browser_directory_;
 
   // Path to the unit test data.
-  FilePath test_data_directory_;
+  base::FilePath test_data_directory_;
 
   // Command to launch the browser
   CommandLine launch_arguments_;
@@ -310,7 +310,7 @@ class UITestBase {
   bool dom_automation_enabled_;
 
   // See set_template_user_data().
-  FilePath template_user_data_;
+  base::FilePath template_user_data_;
 
   // Determines if the window is shown or hidden. Defaults to hidden.
   bool show_window_;
@@ -332,7 +332,7 @@ class UITestBase {
   ProfileType profile_type_;
 
   // PID file for websocket server.
-  FilePath websocket_pid_file_;
+  base::FilePath websocket_pid_file_;
 
  private:
   // Time the test was started (so we can check for new crash dumps)
@@ -377,7 +377,7 @@ class UITest : public UITestBase, public PlatformTest {
   // Apparently needed for Windows buildbots (to workaround an error when
   // file is in use).
   // TODO(phajdan.jr): Move to test_file_util if we need it in more places.
-  bool EvictFileFromSystemCacheWrapper(const FilePath& path);
+  bool EvictFileFromSystemCacheWrapper(const base::FilePath& path);
 
   // Polls the tab for a JavaScript condition and returns once one of the
   // following conditions hold true:
diff --git a/chrome/test/webdriver/webdriver_session.h b/chrome/test/webdriver/webdriver_session.h
index 23395afce12bee..9f02c4ac375dda 100644
--- a/chrome/test/webdriver/webdriver_session.h
+++ b/chrome/test/webdriver/webdriver_session.h
@@ -24,10 +24,9 @@
 #include "chrome/test/webdriver/webdriver_element_id.h"
 #include "chrome/test/webdriver/webdriver_logging.h"
 
-class FilePath;
-
 namespace base {
 class DictionaryValue;
+class FilePath;
 class ListValue;
 class Value;
 class WaitableEvent;
@@ -120,8 +119,9 @@ class Session {
   Error* SendKeys(const string16& keys);
 
   // Sets the file paths to the file upload control under the given location.
-  Error* DragAndDropFilePaths(const Point& location,
-                              const std::vector<FilePath::StringType>& paths);
+  Error* DragAndDropFilePaths(
+      const Point& location,
+      const std::vector<base::FilePath::StringType>& paths);
 
   // Clicks the mouse at the given location using the given button.
   Error* MouseMoveAndClick(const Point& location,
@@ -315,7 +315,7 @@ class Session {
   Error* WaitForAllViewsToStopLoading();
 
   // Install extension at |path|.
-  Error* InstallExtension(const FilePath& path, std::string* extension_id);
+  Error* InstallExtension(const base::FilePath& path, std::string* extension_id);
 
   Error* GetExtensionsInfo(base::ListValue* extension_ids);
 
@@ -393,7 +393,7 @@ class Session {
 
   const Logger& logger() const;
 
-  const FilePath& temp_dir() const;
+  const base::FilePath& temp_dir() const;
 
   const Capabilities& capabilities() const;
 
diff --git a/chrome/test/webdriver/webdriver_util.h b/chrome/test/webdriver/webdriver_util.h
index af01ee9542c5f1..937af221faba90 100644
--- a/chrome/test/webdriver/webdriver_util.h
+++ b/chrome/test/webdriver/webdriver_util.h
@@ -15,9 +15,12 @@
 #include "chrome/test/webdriver/webdriver_error.h"
 
 class AutomationId;
-class FilePath;
 class WebViewId;
 
+namespace base {
+class FilePath;
+}
+
 namespace webdriver {
 
 // Generates a random, 32-character hexidecimal ID.
@@ -30,7 +33,7 @@ bool Base64Decode(const std::string& base64, std::string* bytes);
 
 // Unzip the given zip archive, after base64 decoding, into the given directory.
 // Returns true on success.
-bool Base64DecodeAndUnzip(const FilePath& unzip_dir,
+bool Base64DecodeAndUnzip(const base::FilePath& unzip_dir,
                           const std::string& base64,
                           std::string* error_msg);
 
@@ -40,9 +43,9 @@ bool Base64DecodeAndUnzip(const FilePath& unzip_dir,
 // |file| to the unzipped file.
 // TODO(kkania): Remove the ability to parse single zip file entries when
 // the current versions of all WebDriver clients send actual zip files.
-bool UnzipSoleFile(const FilePath& unzip_dir,
+bool UnzipSoleFile(const base::FilePath& unzip_dir,
                    const std::string& bytes,
-                   FilePath* file,
+                   base::FilePath* file,
                    std::string* error_msg);
 
 // Returns the equivalent JSON string for the given value.
@@ -72,7 +75,7 @@ Error* FlattenStringArray(const ListValue* src, string16* dest);
 
 #if defined(OS_MACOSX)
 // Gets the paths to the user and local application directory.
-void GetApplicationDirs(std::vector<FilePath>* app_dirs);
+void GetApplicationDirs(std::vector<base::FilePath>* app_dirs);
 #endif
 
 // Parses a given value.
diff --git a/chrome/tools/convert_dict/aff_reader.h b/chrome/tools/convert_dict/aff_reader.h
index e353d67ecb97eb..6a1aae8729baa4 100644
--- a/chrome/tools/convert_dict/aff_reader.h
+++ b/chrome/tools/convert_dict/aff_reader.h
@@ -10,13 +10,15 @@
 #include <string>
 #include <vector>
 
+namespace base {
 class FilePath;
+}
 
 namespace convert_dict {
 
 class AffReader {
  public:
-  explicit AffReader(const FilePath& path);
+  explicit AffReader(const base::FilePath& path);
   ~AffReader();
 
   bool Read();
diff --git a/chrome/tools/convert_dict/dic_reader.h b/chrome/tools/convert_dict/dic_reader.h
index 05410bad58670d..74ceafd06edc1c 100644
--- a/chrome/tools/convert_dict/dic_reader.h
+++ b/chrome/tools/convert_dict/dic_reader.h
@@ -10,7 +10,9 @@
 #include <string>
 #include <vector>
 
+namespace base {
 class FilePath;
+}
 
 namespace convert_dict {
 
@@ -25,7 +27,7 @@ class DicReader {
   typedef std::pair<std::string, std::vector<int> > WordEntry;
   typedef std::vector<WordEntry> WordList;
 
-  explicit DicReader(const FilePath& path);
+  explicit DicReader(const base::FilePath& path);
   ~DicReader();
 
   // Non-numeric affixes will be added to the given AffReader and converted into
diff --git a/chrome/utility/chrome_content_utility_client.h b/chrome/utility/chrome_content_utility_client.h
index 5ef6c704b5f360..b28b86e519c3e3 100644
--- a/chrome/utility/chrome_content_utility_client.h
+++ b/chrome/utility/chrome_content_utility_client.h
@@ -11,11 +11,11 @@
 #include "content/public/utility/content_utility_client.h"
 #include "printing/pdf_render_settings.h"
 
-class FilePath;
 class Importer;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 class Thread;
 struct FileDescriptor;
 }
@@ -48,7 +48,7 @@ class ChromeContentUtilityClient : public content::ContentUtilityClient {
   virtual bool Send(IPC::Message* message);
 
   // IPC message handlers.
-  void OnUnpackExtension(const FilePath& extension_path,
+  void OnUnpackExtension(const base::FilePath& extension_path,
                          const std::string& extension_id,
                          int location, int creation_flags);
   void OnUnpackWebResource(const std::string& resource_data);
@@ -57,7 +57,7 @@ class ChromeContentUtilityClient : public content::ContentUtilityClient {
   void OnDecodeImageBase64(const std::string& encoded_data);
   void OnRenderPDFPagesToMetafile(
       base::PlatformFile pdf_file,
-      const FilePath& metafile_path,
+      const base::FilePath& metafile_path,
       const printing::PdfRenderSettings& pdf_render_settings,
       const std::vector<printing::PageRange>& page_ranges);
   void OnRobustJPEGDecodeImage(
@@ -65,8 +65,8 @@ class ChromeContentUtilityClient : public content::ContentUtilityClient {
   void OnParseJSON(const std::string& json);
 
 #if defined(OS_CHROMEOS)
-  void OnCreateZipFile(const FilePath& src_dir,
-                       const std::vector<FilePath>& src_relative_paths,
+  void OnCreateZipFile(const base::FilePath& src_dir,
+                       const std::vector<base::FilePath>& src_relative_paths,
                        const base::FileDescriptor& dest_fd);
 #endif  // defined(OS_CHROMEOS)
 
@@ -75,7 +75,7 @@ class ChromeContentUtilityClient : public content::ContentUtilityClient {
   // |highest_rendered_page_number| is set to -1 on failure to render any page.
   bool RenderPDFToWinMetafile(
       base::PlatformFile pdf_file,
-      const FilePath& metafile_path,
+      const base::FilePath& metafile_path,
       const gfx::Rect& render_area,
       int render_dpi,
       bool autorotate,
diff --git a/chrome_frame/chrome_launcher_utils.h b/chrome_frame/chrome_launcher_utils.h
index a4b79e93cb57ed..d13f4b06497934 100644
--- a/chrome_frame/chrome_launcher_utils.h
+++ b/chrome_frame/chrome_launcher_utils.h
@@ -9,7 +9,10 @@
 #include "base/memory/scoped_ptr.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace chrome_launcher {
 
@@ -35,7 +38,7 @@ bool CreateUpdateCommandLine(const std::wstring& update_command,
                              scoped_ptr<CommandLine>* command_line);
 
 // Returns the full path to the Chrome executable.
-FilePath GetChromeExecutablePath();
+base::FilePath GetChromeExecutablePath();
 
 }  // namespace chrome_launcher
 
diff --git a/chrome_frame/test/chrome_frame_test_utils.h b/chrome_frame/test/chrome_frame_test_utils.h
index f53eefdb8a3d09..59b00efbd661ad 100644
--- a/chrome_frame/test/chrome_frame_test_utils.h
+++ b/chrome_frame/test/chrome_frame_test_utils.h
@@ -37,16 +37,19 @@
 #define GMOCK_MUTANT_INCLUDE_LATE_OBJECT_BINDING
 #include "testing/gmock_mutant.h"
 
-class FilePath;
 interface IWebBrowser2;
 
+namespace base {
+class FilePath;
+}
+
 namespace chrome_frame_test {
 
 int CloseVisibleWindowsOnAllThreads(HANDLE process);
 
 base::ProcessHandle LaunchIE(const std::wstring& url);
 base::ProcessHandle LaunchChrome(const std::wstring& url,
-                                 const FilePath& user_data_dir);
+                                 const base::FilePath& user_data_dir);
 
 // Attempts to close all open IE windows.
 // The return value is the number of windows closed.
@@ -243,7 +246,7 @@ class TimedMsgLoop {
 
  private:
   static void SnapshotAndQuit() {
-    FilePath snapshot;
+    base::FilePath snapshot;
     if (ui_test_utils::SaveScreenSnapshotToDesktop(&snapshot)) {
       testing::UnitTest* unit_test = testing::UnitTest::GetInstance();
       const testing::TestInfo* test_info = unit_test->current_test_info();
@@ -286,7 +289,7 @@ HRESULT LaunchIEAsComServer(IWebBrowser2** web_browser);
 std::wstring GetExecutableAppPath(const std::wstring& file);
 
 // Returns the profile path to be used for IE. This varies as per version.
-FilePath GetProfilePathForIE();
+base::FilePath GetProfilePathForIE();
 
 // Returns the version of the exe passed in.
 std::wstring GetExeVersion(const std::wstring& exe_path);
@@ -295,10 +298,10 @@ std::wstring GetExeVersion(const std::wstring& exe_path);
 IEVersion GetInstalledIEVersion();
 
 // Returns the folder for CF test data.
-FilePath GetTestDataFolder();
+base::FilePath GetTestDataFolder();
 
 // Returns the folder for Selenium core.
-FilePath GetSeleniumTestFolder();
+base::FilePath GetSeleniumTestFolder();
 
 // Returns the path portion of the url.
 std::wstring GetPathFromUrl(const std::wstring& url);
diff --git a/chrome_frame/test_utils.h b/chrome_frame/test_utils.h
index f07bfbed9b1d94..6366ad9813b67b 100644
--- a/chrome_frame/test_utils.h
+++ b/chrome_frame/test_utils.h
@@ -12,7 +12,9 @@
 
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 extern const wchar_t kChromeFrameDllName[];
 extern const wchar_t kChromeLauncherExeName[];
@@ -50,7 +52,7 @@ class ScopedChromeFrameRegistrar {
   static void UnregisterAtPath(const std::wstring& path,
                                RegistrationType registration_type);
   static void RegisterDefaults();
-  static FilePath GetReferenceChromeFrameDllPath();
+  static base::FilePath GetReferenceChromeFrameDllPath();
 
   // Registers or unregisters a COM DLL and exits the process if the process's
   // command line is:
@@ -89,7 +91,7 @@ class ScopedChromeFrameRegistrar {
 // Returns the path to the Chrome Frame DLL in the build directory. Assumes
 // that the test executable is running from the build folder or a similar
 // folder structure.
-FilePath GetChromeFrameBuildPath();
+base::FilePath GetChromeFrameBuildPath();
 
 // Callback description for onload, onloaderror, onmessage
 static _ATL_FUNC_INFO g_single_param = {CC_STDCALL, VT_EMPTY, 1, {VT_VARIANT}};
diff --git a/chrome_frame/utils.h b/chrome_frame/utils.h
index 22045716301136..29084db98d1e23 100644
--- a/chrome_frame/utils.h
+++ b/chrome_frame/utils.h
@@ -20,12 +20,15 @@
 #include "googleurl/src/gurl.h"
 #include "ui/gfx/rect.h"
 
-class FilePath;
 class RegistryListPreferencesHolder;
 interface IBrowserService;
 interface IWebBrowser2;
 struct ContextMenuModel;
 
+namespace base {
+class FilePath;
+}
+
 // utils.h : Various utility functions and classes
 extern const char kGCFProtocol[];
 
@@ -207,7 +210,7 @@ IEVersion GetIEVersion();
 // hosted. Returns 0 if the current process is not IE or any other error occurs.
 uint32 GetIEMajorVersion();
 
-FilePath GetIETemporaryFilesFolder();
+base::FilePath GetIETemporaryFilesFolder();
 
 // Retrieves the file version from a module handle without extra round trips
 // to the disk (as happens with the regular GetFileVersionInfo API).
@@ -601,6 +604,6 @@ bool IncreaseWinInetConnections(DWORD connections);
 // Sets |profile_path| to the path for the Chrome Frame |profile_name|
 // profile.
 void GetChromeFrameProfilePath(const string16& profile_name,
-                               FilePath* profile_path);
+                               base::FilePath* profile_path);
 
 #endif  // CHROME_FRAME_UTILS_H_
diff --git a/chromeos/chromeos_test_utils.cc b/chromeos/chromeos_test_utils.cc
index 3455644aeab9fd..90ee92a9368006 100644
--- a/chromeos/chromeos_test_utils.cc
+++ b/chromeos/chromeos_test_utils.cc
@@ -13,8 +13,8 @@ namespace test_utils {
 
 bool GetTestDataPath(const std::string& component,
                      const std::string& filename,
-                     FilePath* data_dir) {
-  FilePath path;
+                     base::FilePath* data_dir) {
+  base::FilePath path;
   if (!PathService::Get(base::DIR_SOURCE_ROOT, &path))
     return false;
   path = path.Append(FILE_PATH_LITERAL("chromeos"));
diff --git a/chromeos/chromeos_test_utils.h b/chromeos/chromeos_test_utils.h
index b424580bdbaaa3..db0bc661c12b17 100644
--- a/chromeos/chromeos_test_utils.h
+++ b/chromeos/chromeos_test_utils.h
@@ -7,7 +7,9 @@
 
 #include <string>
 
+namespace base {
 class FilePath;
+}
 
 namespace chromeos {
 namespace test_utils {
@@ -15,7 +17,7 @@ namespace test_utils {
 // Returns the path to the given test data file for this library.
 bool GetTestDataPath(const std::string& component,
                      const std::string& filename,
-                     FilePath* data_dir);
+                     base::FilePath* data_dir);
 
 }  // namespace test_utils
 }  // namespace chromeos
diff --git a/cloud_print/service/service_state.h b/cloud_print/service/service_state.h
index ef037bbfb884e3..2c051f6da4bad4 100644
--- a/cloud_print/service/service_state.h
+++ b/cloud_print/service/service_state.h
@@ -7,12 +7,9 @@
 
 #include <string>
 
-#include "base/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 
-class FilePath;
-
 // Manages Cloud Print part of Service State.
 class ServiceState {
  public:
diff --git a/cloud_print/virtual_driver/win/virtual_driver_helpers.h b/cloud_print/virtual_driver/win/virtual_driver_helpers.h
index db59479f6f201c..5380a367cc3bed 100644
--- a/cloud_print/virtual_driver/win/virtual_driver_helpers.h
+++ b/cloud_print/virtual_driver/win/virtual_driver_helpers.h
@@ -6,9 +6,12 @@
 #define CLOUD_PRINT_VIRTUAL_DRIVER_WIN_VIRTUAL_DRIVER_HELPERS_H_
 
 #include <windows.h>
+
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace cloud_print {
 
@@ -27,7 +30,7 @@ HRESULT GetLastHResult();
 string16 GetPortMonitorDllName();
 
 // Gets the standard install path for "version 3" print drivers.
-HRESULT GetPrinterDriverDir(FilePath* path);
+HRESULT GetPrinterDriverDir(base::FilePath* path);
 
 // Retrieves a string from the string table of the module that contains the
 // calling code.
diff --git a/content/browser/appcache/chrome_appcache_service.h b/content/browser/appcache/chrome_appcache_service.h
index 24a509cf12a1b9..e11f3f9897ac17 100644
--- a/content/browser/appcache/chrome_appcache_service.h
+++ b/content/browser/appcache/chrome_appcache_service.h
@@ -13,7 +13,9 @@
 #include "webkit/appcache/appcache_service.h"
 #include "webkit/quota/special_storage_policy.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace net {
 class URLRequestContextGetter;
@@ -44,7 +46,7 @@ class CONTENT_EXPORT ChromeAppCacheService
   explicit ChromeAppCacheService(quota::QuotaManagerProxy* proxy);
 
   void InitializeOnIOThread(
-      const FilePath& cache_path,  // may be empty to use in-memory structures
+      const base::FilePath& cache_path,  // May be empty to use in-memory structs.
       ResourceContext* resource_context,
       net::URLRequestContextGetter* request_context_getter,
       scoped_refptr<quota::SpecialStoragePolicy> special_storage_policy);
@@ -67,7 +69,7 @@ class CONTENT_EXPORT ChromeAppCacheService
   void DeleteOnCorrectThread() const;
 
   ResourceContext* resource_context_;
-  FilePath cache_path_;
+  base::FilePath cache_path_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeAppCacheService);
 };
diff --git a/content/browser/child_process_security_policy_impl.h b/content/browser/child_process_security_policy_impl.h
index a2136b7fee5212..6525968c23d291 100644
--- a/content/browser/child_process_security_policy_impl.h
+++ b/content/browser/child_process_security_policy_impl.h
@@ -17,9 +17,12 @@
 #include "content/public/browser/child_process_security_policy.h"
 #include "webkit/glue/resource_type.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 
 class CONTENT_EXPORT ChildProcessSecurityPolicyImpl
@@ -37,9 +40,9 @@ class CONTENT_EXPORT ChildProcessSecurityPolicyImpl
   virtual void RegisterDisabledSchemes(const std::set<std::string>& schemes)
       OVERRIDE;
   virtual void GrantPermissionsForFile(int child_id,
-                                       const FilePath& file,
+                                       const base::FilePath& file,
                                        int permissions) OVERRIDE;
-  virtual void GrantReadFile(int child_id, const FilePath& file) OVERRIDE;
+  virtual void GrantReadFile(int child_id, const base::FilePath& file) OVERRIDE;
   virtual void GrantReadFileSystem(
       int child_id,
       const std::string& filesystem_id) OVERRIDE;
@@ -50,7 +53,7 @@ class CONTENT_EXPORT ChildProcessSecurityPolicyImpl
       int child_id,
       const std::string& filesystem_id) OVERRIDE;
   virtual void GrantScheme(int child_id, const std::string& scheme) OVERRIDE;
-  virtual bool CanReadFile(int child_id, const FilePath& file) OVERRIDE;
+  virtual bool CanReadFile(int child_id, const base::FilePath& file) OVERRIDE;
   virtual bool CanReadFileSystem(int child_id,
                                  const std::string& filesystem_id) OVERRIDE;
   virtual bool CanReadWriteFileSystem(
@@ -95,10 +98,10 @@ class CONTENT_EXPORT ChildProcessSecurityPolicyImpl
 
   // Grants the child process permission to enumerate all the files in
   // this directory and read those files.
-  void GrantReadDirectory(int child_id, const FilePath& directory);
+  void GrantReadDirectory(int child_id, const base::FilePath& directory);
 
   // Revokes all permissions granted to the given file.
-  void RevokeAllPermissionsForFile(int child_id, const FilePath& file);
+  void RevokeAllPermissionsForFile(int child_id, const base::FilePath& file);
 
   // Grant the child process the ability to use Web UI Bindings.
   void GrantWebUIBindings(int child_id);
@@ -123,12 +126,12 @@ class CONTENT_EXPORT ChildProcessSecurityPolicyImpl
 
   // Before servicing a child process's request to enumerate a directory
   // the browser should call this method to check for the capability.
-  bool CanReadDirectory(int child_id, const FilePath& directory);
+  bool CanReadDirectory(int child_id, const base::FilePath& directory);
 
   // Determines if certain permissions were granted for a file. |permissions|
   // must be a bit-set of base::PlatformFileFlags.
   bool HasPermissionsForFile(int child_id,
-                             const FilePath& file,
+                             const base::FilePath& file,
                              int permissions);
 
   // Returns true if the specified child_id has been granted WebUIBindings.
@@ -194,7 +197,7 @@ class CONTENT_EXPORT ChildProcessSecurityPolicyImpl
   // Determines if certain permissions were granted for a file to given child
   // process. |permissions| must be a bit-set of base::PlatformFileFlags.
   bool ChildProcessHasPermissionsForFile(int child_id,
-                                         const FilePath& file,
+                                         const base::FilePath& file,
                                          int permissions);
 
   // You must acquire this lock before reading or writing any members of this
diff --git a/content/browser/dom_storage/dom_storage_context_impl.h b/content/browser/dom_storage/dom_storage_context_impl.h
index 21f68dfef33cac..a418ea37689c2f 100644
--- a/content/browser/dom_storage/dom_storage_context_impl.h
+++ b/content/browser/dom_storage/dom_storage_context_impl.h
@@ -8,7 +8,9 @@
 #include "base/memory/ref_counted.h"
 #include "content/public/browser/dom_storage_context.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace dom_storage {
 class DomStorageContext;
@@ -27,7 +29,7 @@ class CONTENT_EXPORT DOMStorageContextImpl :
     public base::RefCountedThreadSafe<DOMStorageContextImpl> {
  public:
   // If |data_path| is empty, nothing will be saved to disk.
-  DOMStorageContextImpl(const FilePath& data_path,
+  DOMStorageContextImpl(const base::FilePath& data_path,
                         quota::SpecialStoragePolicy* special_storage_policy);
 
   // DOMStorageContext implementation.
diff --git a/content/browser/download/download_item_factory.h b/content/browser/download/download_item_factory.h
index 5922e6ebb3f885..8104b069e5f650 100644
--- a/content/browser/download/download_item_factory.h
+++ b/content/browser/download/download_item_factory.h
@@ -15,9 +15,12 @@
 #include "content/public/browser/download_id.h"
 #include "content/public/browser/download_item.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace net {
 class BoundNetLog;
 }
@@ -37,7 +40,7 @@ class DownloadItemFactory {
   virtual DownloadItemImpl* CreatePersistedItem(
       DownloadItemImplDelegate* delegate,
       DownloadId download_id,
-      const FilePath& path,
+      const base::FilePath& path,
       const GURL& url,
       const GURL& referrer_url,
       const base::Time& start_time,
@@ -55,7 +58,7 @@ class DownloadItemFactory {
 
   virtual DownloadItemImpl* CreateSavePageItem(
       DownloadItemImplDelegate* delegate,
-      const FilePath& path,
+      const base::FilePath& path,
       const GURL& url,
       DownloadId download_id,
       const std::string& mime_type,
diff --git a/content/browser/download/download_net_log_parameters.h b/content/browser/download/download_net_log_parameters.h
index fc38e9551ad6a0..1c12b8d1767bc5 100644
--- a/content/browser/download/download_net_log_parameters.h
+++ b/content/browser/download/download_net_log_parameters.h
@@ -11,9 +11,12 @@
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 
 enum DownloadType {
@@ -35,8 +38,8 @@ base::Value* ItemCheckedNetLogCallback(
     net::NetLog::LogLevel log_level);
 
 // Returns NetLog parameters when a DownloadItem is renamed.
-base::Value* ItemRenamedNetLogCallback(const FilePath* old_filename,
-                                       const FilePath* new_filename,
+base::Value* ItemRenamedNetLogCallback(const base::FilePath* old_filename,
+                                       const base::FilePath* new_filename,
                                        net::NetLog::LogLevel log_level);
 
 // Returns NetLog parameters when a DownloadItem is interrupted.
@@ -67,7 +70,7 @@ base::Value* ItemCanceledNetLogCallback(int64 bytes_so_far,
                                         net::NetLog::LogLevel log_level);
 
 // Returns NetLog parameters when a DownloadFile is opened.
-base::Value* FileOpenedNetLogCallback(const FilePath* file_name,
+base::Value* FileOpenedNetLogCallback(const base::FilePath* file_name,
                                       int64 start_offset,
                                       net::NetLog::LogLevel log_level);
 
@@ -77,8 +80,8 @@ base::Value* FileStreamDrainedNetLogCallback(size_t stream_size,
                                              net::NetLog::LogLevel log_level);
 
 // Returns NetLog parameters when a DownloadFile is renamed.
-base::Value* FileRenamedNetLogCallback(const FilePath* old_filename,
-                                       const FilePath* new_filename,
+base::Value* FileRenamedNetLogCallback(const base::FilePath* old_filename,
+                                       const base::FilePath* new_filename,
                                        net::NetLog::LogLevel log_level);
 
 // Returns NetLog parameters when a File has an error.
diff --git a/content/browser/download/drag_download_util.h b/content/browser/download/drag_download_util.h
index c968ae4fb0b5ba..c6568c971b68c9 100644
--- a/content/browser/download/drag_download_util.h
+++ b/content/browser/download/drag_download_util.h
@@ -11,8 +11,12 @@
 #include "content/browser/download/drag_download_file.h"
 #include "ui/base/dragdrop/download_file_interface.h"
 
-class FilePath;
 class GURL;
+
+namespace base {
+class FilePath;
+}
+
 namespace net {
 class FileStream;
 }
@@ -30,7 +34,7 @@ namespace content {
 //   text/plain:example.txt:http://example.com/example.txt
 bool ParseDownloadMetadata(const string16& metadata,
                            string16* mime_type,
-                           FilePath* file_name,
+                           base::FilePath* file_name,
                            GURL* url);
 
 // Create a new file at the specified path. If the file already exists, try to
@@ -38,7 +42,7 @@ bool ParseDownloadMetadata(const string16& metadata,
 // Return a FileStream if successful.
 // |net_log| is a NetLog for the stream.
 CONTENT_EXPORT net::FileStream* CreateFileStreamForDrop(
-    FilePath* file_path, net::NetLog* net_log);
+    base::FilePath* file_path, net::NetLog* net_log);
 
 // Implementation of DownloadFileObserver to finalize the download process.
 class PromiseFileFinalizer : public ui::DownloadFileObserver {
@@ -46,7 +50,7 @@ class PromiseFileFinalizer : public ui::DownloadFileObserver {
   explicit PromiseFileFinalizer(DragDownloadFile* drag_file_downloader);
 
   // DownloadFileObserver methods.
-  virtual void OnDownloadCompleted(const FilePath& file_path) OVERRIDE;
+  virtual void OnDownloadCompleted(const base::FilePath& file_path) OVERRIDE;
   virtual void OnDownloadAborted() OVERRIDE;
 
  protected:
diff --git a/content/browser/download/file_metadata_linux.h b/content/browser/download/file_metadata_linux.h
index 5494add1f9b4bd..c4fc3045c41f24 100644
--- a/content/browser/download/file_metadata_linux.h
+++ b/content/browser/download/file_metadata_linux.h
@@ -7,9 +7,12 @@
 
 #include "content/common/content_export.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 
 // The source URL attribute is part of the XDG standard.
@@ -22,7 +25,7 @@ CONTENT_EXPORT extern const char kReferrerURLAttrName[];
 // Adds origin metadata to the file.
 // |source| should be the source URL for the download, and |referrer| should be
 // the URL the user initiated the download from.
-CONTENT_EXPORT void AddOriginMetadataToFile(const FilePath& file,
+CONTENT_EXPORT void AddOriginMetadataToFile(const base::FilePath& file,
                                             const GURL& source,
                                             const GURL& referrer);
 
diff --git a/content/browser/download/file_metadata_mac.h b/content/browser/download/file_metadata_mac.h
index 7d63a3c58392f4..19a3f07ff62a84 100644
--- a/content/browser/download/file_metadata_mac.h
+++ b/content/browser/download/file_metadata_mac.h
@@ -5,22 +5,25 @@
 #ifndef CONTENT_BROWSER_DOWNLOAD_FILE_METADATA_MAC_H_
 #define CONTENT_BROWSER_DOWNLOAD_FILE_METADATA_MAC_H_
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 
 // Adds origin metadata to the file.
 // |source| should be the source URL for the download, and |referrer| should be
 // the URL the user initiated the download from.
-void AddOriginMetadataToFile(const FilePath& file, const GURL& source,
+void AddOriginMetadataToFile(const base::FilePath& file, const GURL& source,
                              const GURL& referrer);
 
 // Adds quarantine metadata to the file, assuming it has already been
 // quarantined by the OS.
 // |source| should be the source URL for the download, and |referrer| should be
 // the URL the user initiated the download from.
-void AddQuarantineMetadataToFile(const FilePath& file, const GURL& source,
+void AddQuarantineMetadataToFile(const base::FilePath& file, const GURL& source,
                                  const GURL& referrer);
 
 }  // namespace content
diff --git a/content/browser/download/mhtml_generation_manager.h b/content/browser/download/mhtml_generation_manager.h
index 54b8733dd3c3ce..ffdb95b680a539 100644
--- a/content/browser/download/mhtml_generation_manager.h
+++ b/content/browser/download/mhtml_generation_manager.h
@@ -12,7 +12,9 @@
 #include "base/process.h"
 #include "ipc/ipc_platform_file.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 class WebContents;
@@ -21,13 +23,13 @@ class MHTMLGenerationManager {
  public:
   static MHTMLGenerationManager* GetInstance();
 
-  typedef base::Callback<void(const FilePath& /* path to the MHTML file */,
+  typedef base::Callback<void(const base::FilePath& /* path to the MHTML file */,
       int64 /* size of the file */)> GenerateMHTMLCallback;
 
   // Instructs the render view to generate a MHTML representation of the current
   // page for |web_contents|.
   void GenerateMHTML(WebContents* web_contents,
-                     const FilePath& file,
+                     const base::FilePath& file,
                      const GenerateMHTMLCallback& callback);
 
   // Notification from the renderer that the MHTML generation finished.
@@ -42,7 +44,7 @@ class MHTMLGenerationManager {
     Job();
     ~Job();
 
-    FilePath file_path;
+    base::FilePath file_path;
 
     // The handles to file the MHTML is saved to, for the browser and renderer
     // processes.
@@ -62,7 +64,7 @@ class MHTMLGenerationManager {
 
   // Called on the file thread to create |file|.
   void CreateFile(int job_id,
-                  const FilePath& file,
+                  const base::FilePath& file,
                   base::ProcessHandle renderer_process);
 
   // Called on the UI thread when the file that should hold the MHTML data has
diff --git a/content/browser/download/save_file_manager.h b/content/browser/download/save_file_manager.h
index 73c77117fb2fd5..8e3523e696a326 100644
--- a/content/browser/download/save_file_manager.h
+++ b/content/browser/download/save_file_manager.h
@@ -66,9 +66,11 @@
 #include "content/browser/download/save_types.h"
 #include "content/common/content_export.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
 
 namespace net {
 class IOBuffer;
@@ -99,7 +101,7 @@ class SaveFileManager : public base::RefCountedThreadSafe<SaveFileManager> {
                int render_process_host_id,
                int render_view_id,
                SaveFileCreateInfo::SaveFileSource save_source,
-               const FilePath& file_full_path,
+               const base::FilePath& file_full_path,
                ResourceContext* context,
                SavePackage* save_package);
 
@@ -121,7 +123,7 @@ class SaveFileManager : public base::RefCountedThreadSafe<SaveFileManager> {
                       SavePackage* package);
 
   // Helper function for deleting specified file.
-  void DeleteDirectoryOrFile(const FilePath& full_path, bool is_dir);
+  void DeleteDirectoryOrFile(const base::FilePath& full_path, bool is_dir);
 
   // Runs on file thread to save a file by copying from file system when
   // original url is using file scheme.
@@ -134,7 +136,7 @@ class SaveFileManager : public base::RefCountedThreadSafe<SaveFileManager> {
   // final names of successfully saved files.
   void RenameAllFiles(
       const FinalNameList& final_names,
-      const FilePath& resource_dir,
+      const base::FilePath& resource_dir,
       int render_process_id,
       int render_view_id,
       int save_package_id);
@@ -199,7 +201,7 @@ class SaveFileManager : public base::RefCountedThreadSafe<SaveFileManager> {
   // Notifications sent from the UI thread and run on the file thread.
 
   // Deletes a specified file on the file thread.
-  void OnDeleteDirectoryOrFile(const FilePath& full_path, bool is_dir);
+  void OnDeleteDirectoryOrFile(const base::FilePath& full_path, bool is_dir);
 
   // Notifications sent from the UI thread and run on the IO thread
 
diff --git a/content/browser/fileapi/fileapi_message_filter.h b/content/browser/fileapi/fileapi_message_filter.h
index 610fed1486e4b0..c0c6990fa5547b 100644
--- a/content/browser/fileapi/fileapi_message_filter.h
+++ b/content/browser/fileapi/fileapi_message_filter.h
@@ -18,10 +18,10 @@
 #include "webkit/blob/blob_data.h"
 #include "webkit/fileapi/file_system_types.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -113,7 +113,7 @@ class FileAPIMessageFilter : public BrowserMessageFilter {
   void OnWillUpdate(const GURL& path);
   void OnDidUpdate(const GURL& path, int64 delta);
   void OnSyncGetPlatformPath(const GURL& path,
-                             FilePath* platform_path);
+                             base::FilePath* platform_path);
   void OnCreateSnapshotFile(int request_id,
                             const GURL& blob_url,
                             const GURL& path);
@@ -133,7 +133,7 @@ class FileAPIMessageFilter : public BrowserMessageFilter {
   void DidGetMetadata(int request_id,
                       base::PlatformFileError result,
                       const base::PlatformFileInfo& info,
-                      const FilePath& platform_path);
+                      const base::FilePath& platform_path);
   void DidReadDirectory(int request_id,
                         base::PlatformFileError result,
                         const std::vector<base::FileUtilProxy::Entry>& entries,
@@ -155,17 +155,17 @@ class FileAPIMessageFilter : public BrowserMessageFilter {
                            base::PlatformFileError result);
   void DidCreateSnapshot(
       int request_id,
-      const base::Callback<void(const FilePath&)>& register_file_callback,
+      const base::Callback<void(const base::FilePath&)>& register_file_callback,
       base::PlatformFileError result,
       const base::PlatformFileInfo& info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
 
   // Registers the given file pointed by |virtual_path| and backed by
   // |platform_path| as the |blob_url|.  Called by DidCreateSnapshot.
   void RegisterFileAsBlob(const GURL& blob_url,
                           const fileapi::FileSystemURL& url,
-                          const FilePath& platform_path);
+                          const base::FilePath& platform_path);
 
   // Checks renderer's access permissions for single file.
   bool HasPermissionsForFile(const fileapi::FileSystemURL& url,
diff --git a/content/browser/in_process_webkit/indexed_db_context_impl.h b/content/browser/in_process_webkit/indexed_db_context_impl.h
index 11a3a680c001d3..e8a2a7c0f3d762 100644
--- a/content/browser/in_process_webkit/indexed_db_context_impl.h
+++ b/content/browser/in_process_webkit/indexed_db_context_impl.h
@@ -17,7 +17,6 @@
 #include "webkit/quota/quota_types.h"
 
 class GURL;
-class FilePath;
 
 namespace WebKit {
 class WebIDBDatabase;
@@ -25,6 +24,7 @@ class WebIDBFactory;
 }
 
 namespace base {
+class FilePath;
 class MessageLoopProxy;
 }
 
@@ -39,7 +39,7 @@ class CONTENT_EXPORT IndexedDBContextImpl
     : NON_EXPORTED_BASE(public IndexedDBContext) {
  public:
   // If |data_path| is empty, nothing will be saved to disk.
-  IndexedDBContextImpl(const FilePath& data_path,
+  IndexedDBContextImpl(const base::FilePath& data_path,
                        quota::SpecialStoragePolicy* special_storage_policy,
                        quota::QuotaManagerProxy* quota_manager_proxy,
                        base::MessageLoopProxy* webkit_thread_loop);
@@ -47,10 +47,10 @@ class CONTENT_EXPORT IndexedDBContextImpl
   WebKit::WebIDBFactory* GetIDBFactory();
 
   // The indexed db directory.
-  static const FilePath::CharType kIndexedDBDirectory[];
+  static const base::FilePath::CharType kIndexedDBDirectory[];
 
   // The indexed db file extension.
-  static const FilePath::CharType kIndexedDBExtension[];
+  static const base::FilePath::CharType kIndexedDBExtension[];
 
   // Disables the exit-time deletion of session-only data.
   void SetForceKeepSessionState() {
@@ -62,7 +62,7 @@ class CONTENT_EXPORT IndexedDBContextImpl
   virtual int64 GetOriginDiskUsage(const GURL& origin_url) OVERRIDE;
   virtual base::Time GetOriginLastModified(const GURL& origin_url) OVERRIDE;
   virtual void DeleteForOrigin(const GURL& origin_url) OVERRIDE;
-  virtual FilePath GetFilePathForTesting(
+  virtual base::FilePath GetFilePathForTesting(
       const string16& origin_id) const OVERRIDE;
 
   // Methods called by IndexedDBDispatcherHost for quota support.
@@ -74,10 +74,10 @@ class CONTENT_EXPORT IndexedDBContextImpl
 
   quota::QuotaManagerProxy* quota_manager_proxy();
 
-  FilePath data_path() const { return data_path_; }
+  base::FilePath data_path() const { return data_path_; }
 
   // For unit tests allow to override the |data_path_|.
-  void set_data_path_for_testing(const FilePath& data_path) {
+  void set_data_path_for_testing(const base::FilePath& data_path) {
     data_path_ = data_path;
   }
 
@@ -94,7 +94,7 @@ class CONTENT_EXPORT IndexedDBContextImpl
   typedef std::map<GURL, int64> OriginToSizeMap;
   class IndexedDBGetUsageAndQuotaCallback;
 
-  FilePath GetIndexedDBFilePath(const string16& origin_id) const;
+  base::FilePath GetIndexedDBFilePath(const string16& origin_id) const;
   int64 ReadUsageFromDisk(const GURL& origin_url) const;
   void EnsureDiskUsageCacheInitialized(const GURL& origin_url);
   void QueryDiskAndUpdateQuotaUsage(const GURL& origin_url);
@@ -119,7 +119,7 @@ class CONTENT_EXPORT IndexedDBContextImpl
   void ResetCaches();
 
   scoped_ptr<WebKit::WebIDBFactory> idb_factory_;
-  FilePath data_path_;
+  base::FilePath data_path_;
   // If true, nothing (not even session-only data) should be deleted on exit.
   bool force_keep_session_state_;
   scoped_refptr<quota::SpecialStoragePolicy> special_storage_policy_;
diff --git a/content/browser/safe_util_win.h b/content/browser/safe_util_win.h
index a8cb077ed4ff13..16367488b3adac 100644
--- a/content/browser/safe_util_win.h
+++ b/content/browser/safe_util_win.h
@@ -8,9 +8,12 @@
 #include <string>
 #include <windows.h>
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 
 // Open or run a downloaded file via the Windows shell, possibly showing first
@@ -38,7 +41,7 @@ namespace content {
 // dialog.
 // Returns 'true' on successful open, 'false' otherwise.
 bool SaferOpenItemViaShell(HWND hwnd, const std::wstring& window_title,
-                           const FilePath& full_path,
+                           const base::FilePath& full_path,
                            const std::wstring& source_url);
 
 // Invokes IAttachmentExecute::Save to validate the downloaded file. The call
@@ -66,7 +69,7 @@ bool SaferOpenItemViaShell(HWND hwnd, const std::wstring& window_title,
 // |full_path| : is the path to the downloaded file. This should be the final
 //               path of the download.
 // |source_url|: the source URL for the download.
-HRESULT ScanAndSaveDownloadedFile(const FilePath& full_path,
+HRESULT ScanAndSaveDownloadedFile(const base::FilePath& full_path,
                                   const GURL& source_url);
 }  // namespace content
 
diff --git a/content/browser/storage_partition_impl_map.h b/content/browser/storage_partition_impl_map.h
index 196a388eaeed7a..7f69dea489e0f0 100644
--- a/content/browser/storage_partition_impl_map.h
+++ b/content/browser/storage_partition_impl_map.h
@@ -15,9 +15,8 @@
 #include "content/browser/storage_partition_impl.h"
 #include "content/public/browser/browser_context.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }  // namespace base
 
@@ -51,7 +50,7 @@ class StoragePartitionImplMap : public base::SupportsUserData::Data {
   //
   // The |done| closure is executed on the calling thread when garbage
   // collection is complete.
-  void GarbageCollect(scoped_ptr<base::hash_set<FilePath> > active_paths,
+  void GarbageCollect(scoped_ptr<base::hash_set<base::FilePath> > active_paths,
                       const base::Closure& done);
 
   void ForEach(const BrowserContext::StoragePartitionCallback& callback);
@@ -106,8 +105,9 @@ class StoragePartitionImplMap : public base::SupportsUserData::Data {
   // Returns the relative path from the profile's base directory, to the
   // directory that holds all the state for storage contexts in the given
   // |partition_domain| and |partition_name|.
-  static FilePath GetStoragePartitionPath(const std::string& partition_domain,
-                                          const std::string& partition_name);
+  static base::FilePath GetStoragePartitionPath(
+      const std::string& partition_domain,
+      const std::string& partition_name);
 
   // This must always be called *after* |partition| has been added to the
   // partitions_.
diff --git a/content/common/child_process_host_impl.h b/content/common/child_process_host_impl.h
index fe34911aed4c95..be2ea1e0b6c4fa 100644
--- a/content/common/child_process_host_impl.h
+++ b/content/common/child_process_host_impl.h
@@ -18,7 +18,9 @@
 #include "ipc/ipc_listener.h"
 #include "content/public/common/child_process_host.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 class ChildProcessHostDelegate;
diff --git a/content/common/fileapi/file_system_dispatcher.h b/content/common/fileapi/file_system_dispatcher.h
index 99afa50e65aa78..4d1171b4ee52e8 100644
--- a/content/common/fileapi/file_system_dispatcher.h
+++ b/content/common/fileapi/file_system_dispatcher.h
@@ -18,10 +18,10 @@
 #include "webkit/fileapi/file_system_types.h"
 
 namespace base {
+class FilePath;
 struct PlatformFileInfo;
 }
 
-class FilePath;
 class GURL;
 
 namespace content {
@@ -102,7 +102,7 @@ class FileSystemDispatcher : public IPC::Listener {
   void OnDidSucceed(int request_id);
   void OnDidReadMetadata(int request_id,
                          const base::PlatformFileInfo& file_info,
-                         const FilePath& platform_path);
+                         const base::FilePath& platform_path);
   void OnDidReadDirectory(
       int request_id,
       const std::vector<base::FileUtilProxy::Entry>& entries,
diff --git a/content/common/sandbox_mac.h b/content/common/sandbox_mac.h
index d28fdf7796d2aa..ea23ce521b490c 100644
--- a/content/common/sandbox_mac.h
+++ b/content/common/sandbox_mac.h
@@ -13,7 +13,9 @@
 #include "content/common/content_export.h"
 #include "content/public/common/sandbox_type_mac.h"
 
+namespace base {
 class FilePath;
+}
 
 #if __OBJC__
 @class NSArray;
@@ -73,7 +75,7 @@ class CONTENT_EXPORT Sandbox {
   //
   // Returns true on success, false if an error occurred enabling the sandbox.
   static bool EnableSandbox(int sandbox_type,
-                            const FilePath& allowed_dir);
+                            const base::FilePath& allowed_dir);
 
 
   // Exposed for testing purposes, used by an accessory function of our tests
@@ -89,7 +91,7 @@ class CONTENT_EXPORT Sandbox {
   // The returned string contains embedded variables. The function fills in
   // |substitutions| to contain the values for these variables.
   static NSString* BuildAllowDirectoryAccessSandboxString(
-                       const FilePath& allowed_dir,
+                       const base::FilePath& allowed_dir,
                        SandboxVariableSubstitions* substitutions);
 
   // Assemble the final sandbox profile from a template by removing comments
@@ -126,7 +128,7 @@ class CONTENT_EXPORT Sandbox {
  private:
   // Returns an (allow file-read-metadata) rule for |allowed_path| and all its
   // parent directories.
-  static NSString* AllowMetadataForPath(const FilePath& allowed_path);
+  static NSString* AllowMetadataForPath(const base::FilePath& allowed_path);
 
   // Escape |src_utf8| for use in a plain string variable in a sandbox
   // configuraton file.  On return |dst| is set to the quoted output.
@@ -151,7 +153,7 @@ class CONTENT_EXPORT Sandbox {
   // Convert provided path into a "canonical" path matching what the Sandbox
   // expects i.e. one without symlinks.
   // This path is not necessarily unique e.g. in the face of hardlinks.
-  static FilePath GetCanonicalSandboxPath(const FilePath& path);
+  static base::FilePath GetCanonicalSandboxPath(const base::FilePath& path);
 
   FRIEND_TEST_ALL_PREFIXES(MacDirAccessSandboxTest, StringEscape);
   FRIEND_TEST_ALL_PREFIXES(MacDirAccessSandboxTest, RegexEscape);
diff --git a/content/ppapi_plugin/ppapi_thread.h b/content/ppapi_plugin/ppapi_thread.h
index d7fd03995e2ab7..0e21d5611ea7b5 100644
--- a/content/ppapi_plugin/ppapi_thread.h
+++ b/content/ppapi_plugin/ppapi_thread.h
@@ -28,7 +28,10 @@
 #endif
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace IPC {
 struct ChannelHandle;
@@ -88,7 +91,7 @@ class PpapiThread : public ChildThread,
   virtual void SetActiveURL(const std::string& url) OVERRIDE;
 
   // Message handlers.
-  void OnLoadPlugin(const FilePath& path,
+  void OnLoadPlugin(const base::FilePath& path,
                     const ppapi::PpapiPermissions& permissions);
   void OnCreateChannel(base::ProcessId renderer_pid,
                        int renderer_child_id,
@@ -108,7 +111,7 @@ class PpapiThread : public ChildThread,
                             IPC::ChannelHandle* handle);
 
   // Sets up the name of the plugin for logging using the given path.
-  void SavePluginName(const FilePath& path);
+  void SavePluginName(const base::FilePath& path);
 
   // True if running in a broker process rather than a normal plugin process.
   bool is_broker_;
diff --git a/content/public/browser/browser_child_process_host.h b/content/public/browser/browser_child_process_host.h
index e56404ddc8c503..d1bbb81f86de50 100644
--- a/content/public/browser/browser_child_process_host.h
+++ b/content/public/browser/browser_child_process_host.h
@@ -13,7 +13,10 @@
 #include "ipc/ipc_sender.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace content {
 
@@ -36,7 +39,7 @@ class CONTENT_EXPORT BrowserChildProcessHost : public IPC::Sender {
   // Takes ownership of |cmd_line|.
   virtual void Launch(
 #if defined(OS_WIN)
-      const FilePath& exposed_dir,
+      const base::FilePath& exposed_dir,
 #elif defined(OS_POSIX)
       bool use_zygote,
       const base::EnvironmentVector& environ,
diff --git a/content/public/browser/browser_context.h b/content/public/browser/browser_context.h
index 1bd59494fab136..d82326af349346 100644
--- a/content/public/browser/browser_context.h
+++ b/content/public/browser/browser_context.h
@@ -11,6 +11,12 @@
 #include "base/supports_user_data.h"
 #include "content/common/content_export.h"
 
+class GURL;
+
+namespace base {
+class FilePath;
+}
+
 namespace fileapi {
 class ExternalMountPoints;
 }
@@ -23,9 +29,6 @@ namespace quota {
 class SpecialStoragePolicy;
 }
 
-class FilePath;
-class GURL;
-
 namespace content {
 
 class DownloadManager;
@@ -69,7 +72,7 @@ class CONTENT_EXPORT BrowserContext : public base::SupportsUserData {
   // ownership of the pointer.
   static void GarbageCollectStoragePartitions(
       BrowserContext* browser_context,
-      scoped_ptr<base::hash_set<FilePath> > active_paths,
+      scoped_ptr<base::hash_set<base::FilePath> > active_paths,
       const base::Closure& done);
 
   // DON'T USE THIS. GetDefaultStoragePartition() is going away.
@@ -94,7 +97,7 @@ class CONTENT_EXPORT BrowserContext : public base::SupportsUserData {
   virtual ~BrowserContext();
 
   // Returns the path of the directory where this context's data is stored.
-  virtual FilePath GetPath() = 0;
+  virtual base::FilePath GetPath() = 0;
 
   // Return whether this context is incognito. Default is false.
   // This doesn't belong here; http://crbug.com/89628
@@ -114,7 +117,7 @@ class CONTENT_EXPORT BrowserContext : public base::SupportsUserData {
       int renderer_child_id) = 0;
 
   virtual net::URLRequestContextGetter* GetRequestContextForStoragePartition(
-      const FilePath& partition_path,
+      const base::FilePath& partition_path,
       bool in_memory) = 0;
 
   // Returns the default request context for media resources associated with
@@ -128,7 +131,7 @@ class CONTENT_EXPORT BrowserContext : public base::SupportsUserData {
       int renderer_child_id) = 0;
   virtual net::URLRequestContextGetter*
       GetMediaRequestContextForStoragePartition(
-          const FilePath& partition_path,
+          const base::FilePath& partition_path,
           bool in_memory) = 0;
 
   // Returns the resource context.
diff --git a/content/public/browser/browser_ppapi_host.h b/content/public/browser/browser_ppapi_host.h
index ac62a07b749be8..d23908e01c8032 100644
--- a/content/public/browser/browser_ppapi_host.h
+++ b/content/public/browser/browser_ppapi_host.h
@@ -77,7 +77,7 @@ class CONTENT_EXPORT BrowserPpapiHost {
   virtual const std::string& GetPluginName() = 0;
 
   // Returns the user's profile data directory.
-  virtual const FilePath& GetProfileDataDirectory() = 0;
+  virtual const base::FilePath& GetProfileDataDirectory() = 0;
 
   // Get the Document/Plugin URLs for the given PP_Instance.
   virtual GURL GetDocumentURLForInstance(PP_Instance instance) = 0;
diff --git a/content/public/browser/child_process_security_policy.h b/content/public/browser/child_process_security_policy.h
index 189effabcf4938..b56f7f87a71696 100644
--- a/content/public/browser/child_process_security_policy.h
+++ b/content/public/browser/child_process_security_policy.h
@@ -11,7 +11,9 @@
 #include "base/basictypes.h"
 #include "content/common/content_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 
@@ -49,18 +51,18 @@ class ChildProcessSecurityPolicy {
   // Grants certain permissions to a file. |permissions| must be a bit-set of
   // base::PlatformFileFlags.
   virtual void GrantPermissionsForFile(int child_id,
-                                       const FilePath& file,
+                                       const base::FilePath& file,
                                        int permissions) = 0;
 
   // Before servicing a child process's request to upload a file to the web, the
   // browser should call this method to determine whether the process has the
   // capability to upload the requested file.
-  virtual bool CanReadFile(int child_id, const FilePath& file) = 0;
+  virtual bool CanReadFile(int child_id, const base::FilePath& file) = 0;
 
   // Whenever the user picks a file from a <input type="file"> element, the
   // browser should call this function to grant the child process the capability
   // to upload the file to the web.
-  virtual void GrantReadFile(int child_id, const FilePath& file) = 0;
+  virtual void GrantReadFile(int child_id, const base::FilePath& file) = 0;
 
   // Grants read access permission to the given isolated file system
   // identified by |filesystem_id|. An isolated file system can be
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index 9b5fea3f9d5084..b332073a9cb9cb 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -23,9 +23,12 @@
 #endif
 
 class CommandLine;
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace webkit_glue {
 struct WebPreferences;
 }
diff --git a/content/public/browser/download_item.h b/content/public/browser/download_item.h
index 2d4c5a8709a74f..3e29c07543799a 100644
--- a/content/public/browser/download_item.h
+++ b/content/public/browser/download_item.h
@@ -28,10 +28,10 @@
 #include "content/public/browser/download_interrupt_reasons.h"
 #include "content/public/common/page_transition_types.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class Time;
 class TimeDelta;
 }
diff --git a/content/public/browser/gpu_data_manager.h b/content/public/browser/gpu_data_manager.h
index c89e9be06b2437..ebe56d62e22a3a 100644
--- a/content/public/browser/gpu_data_manager.h
+++ b/content/public/browser/gpu_data_manager.h
@@ -13,10 +13,10 @@
 #include "content/public/common/gpu_feature_type.h"
 #include "content/public/common/gpu_switching_option.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class ListValue;
 }
 
@@ -66,7 +66,7 @@ class GpuDataManager {
   virtual bool ShouldUseSoftwareRendering() const = 0;
 
   // Register a path to the SwiftShader software renderer.
-  virtual void RegisterSwiftShaderPath(const FilePath& path) = 0;
+  virtual void RegisterSwiftShaderPath(const base::FilePath& path) = 0;
 
   // Registers/unregister |observer|.
   virtual void AddObserver(GpuDataManagerObserver* observer) = 0;
diff --git a/content/public/browser/pepper_flash_settings_helper.h b/content/public/browser/pepper_flash_settings_helper.h
index 7fb4cc41fd79c7..72f069d8ab450e 100644
--- a/content/public/browser/pepper_flash_settings_helper.h
+++ b/content/public/browser/pepper_flash_settings_helper.h
@@ -9,7 +9,9 @@
 #include "base/memory/ref_counted.h"
 #include "content/common/content_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace IPC {
 struct ChannelHandle;
@@ -29,7 +31,7 @@ class CONTENT_EXPORT PepperFlashSettingsHelper
   typedef base::Callback<void(bool /* success */,
                               const IPC::ChannelHandle& /* channel_handle */)>
       OpenChannelCallback;
-  virtual void OpenChannelToBroker(const FilePath& path,
+  virtual void OpenChannelToBroker(const base::FilePath& path,
                                    const OpenChannelCallback& callback) = 0;
 
  protected:
diff --git a/content/public/browser/plugin_service.h b/content/public/browser/plugin_service.h
index 73641951785d44..f8d5e891567092 100644
--- a/content/public/browser/plugin_service.h
+++ b/content/public/browser/plugin_service.h
@@ -12,9 +12,12 @@
 #include "base/string16.h"
 #include "content/common/content_export.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace webkit {
 struct WebPluginInfo;
 namespace npapi {
@@ -86,13 +89,14 @@ class PluginService {
   // Get plugin info by plugin path (including disabled plugins). Returns true
   // if the plugin is found and WebPluginInfo has been filled in |info|. This
   // will use cached data in the plugin list.
-  virtual bool GetPluginInfoByPath(const FilePath& plugin_path,
+  virtual bool GetPluginInfoByPath(const base::FilePath& plugin_path,
                                    webkit::WebPluginInfo* info) = 0;
 
   // Returns the display name for the plugin identified by the given path. If
   // the path doesn't identify a plugin, or the plugin has no display name,
   // this will attempt to generate a display name from the path.
-  virtual string16 GetPluginDisplayNameByPath(const FilePath& plugin_path) = 0;
+  virtual string16 GetPluginDisplayNameByPath(
+      const base::FilePath& plugin_path) = 0;
 
   // Asynchronously loads plugins if necessary and then calls back to the
   // provided function on the calling MessageLoop on completion.
@@ -102,17 +106,17 @@ class PluginService {
   // The caller does not own the pointer, and it's not guaranteed to live past
   // the call stack.
   virtual PepperPluginInfo* GetRegisteredPpapiPluginInfo(
-      const FilePath& plugin_path) = 0;
+      const base::FilePath& plugin_path) = 0;
 
   virtual void SetFilter(PluginServiceFilter* filter) = 0;
   virtual PluginServiceFilter* GetFilter() = 0;
 
   // If the plugin with the given path is running, cleanly shuts it down.
-  virtual void ForcePluginShutdown(const FilePath& plugin_path) = 0;
+  virtual void ForcePluginShutdown(const base::FilePath& plugin_path) = 0;
 
   // Used to monitor plug-in stability. An unstable plug-in is one that has
   // crashed more than a set number of times in a set time period.
-  virtual bool IsPluginUnstable(const FilePath& plugin_path) = 0;
+  virtual bool IsPluginUnstable(const base::FilePath& plugin_path) = 0;
 
   // The following functions are wrappers around webkit::npapi::PluginList.
   // These must be used instead of those in order to ensure that we have a
@@ -120,10 +124,10 @@ class PluginService {
   // accidentally load plugins in the wrong process or thread. Refer to
   // PluginList for further documentation of these functions.
   virtual void RefreshPlugins() = 0;
-  virtual void AddExtraPluginPath(const FilePath& path) = 0;
-  virtual void AddExtraPluginDir(const FilePath& path) = 0;
-  virtual void RemoveExtraPluginPath(const FilePath& path) = 0;
-  virtual void UnregisterInternalPlugin(const FilePath& path) = 0;
+  virtual void AddExtraPluginPath(const base::FilePath& path) = 0;
+  virtual void AddExtraPluginDir(const base::FilePath& path) = 0;
+  virtual void RemoveExtraPluginPath(const base::FilePath& path) = 0;
+  virtual void UnregisterInternalPlugin(const base::FilePath& path) = 0;
   virtual void RegisterInternalPlugin(const webkit::WebPluginInfo& info,
                                       bool add_at_beginning) = 0;
   virtual void GetInternalPlugins(
diff --git a/content/public/browser/render_view_host.h b/content/public/browser/render_view_host.h
index c92e9269aa2cd4..10f7724667ab83 100644
--- a/content/public/browser/render_view_host.h
+++ b/content/public/browser/render_view_host.h
@@ -12,7 +12,6 @@
 #include "content/public/common/stop_find_action.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDragOperation.h"
 
-class FilePath;
 class GURL;
 struct WebDropData;
 
@@ -21,6 +20,7 @@ class Point;
 }
 
 namespace base {
+class FilePath;
 class Value;
 }
 
@@ -113,7 +113,7 @@ class CONTENT_EXPORT RenderViewHost : virtual public RenderWidgetHost {
   // Notifies the listener that a directory enumeration is complete.
   virtual void DirectoryEnumerationFinished(
       int request_id,
-      const std::vector<FilePath>& files) = 0;
+      const std::vector<base::FilePath>& files) = 0;
 
   // Tells the renderer not to add scrollbars with height and width below a
   // threshold.
diff --git a/content/public/browser/utility_process_host.h b/content/public/browser/utility_process_host.h
index 240fbe55b8eb2c..5f280c6d58a526 100644
--- a/content/public/browser/utility_process_host.h
+++ b/content/public/browser/utility_process_host.h
@@ -9,9 +9,8 @@
 #include "content/common/content_export.h"
 #include "ipc/ipc_sender.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }
 
@@ -49,7 +48,7 @@ class UtilityProcessHost : public IPC::Sender,
 
   // Allows a directory to be opened through the sandbox, in case it's needed by
   // the operation.
-  virtual void SetExposedDir(const FilePath& dir) = 0;
+  virtual void SetExposedDir(const base::FilePath& dir) = 0;
 
   // Make the process run without a sandbox.
   virtual void DisableSandbox() = 0;
diff --git a/content/public/browser/web_contents_delegate.h b/content/public/browser/web_contents_delegate.h
index ba57196e1c9f52..63e6380a7caa74 100644
--- a/content/public/browser/web_contents_delegate.h
+++ b/content/public/browser/web_contents_delegate.h
@@ -21,10 +21,10 @@
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect_f.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class ListValue;
 }
 
@@ -336,7 +336,7 @@ class CONTENT_EXPORT WebContentsDelegate {
   // directory.
   virtual void EnumerateDirectory(WebContents* web_contents,
                                   int request_id,
-                                  const FilePath& path) {}
+                                  const base::FilePath& path) {}
 
   // Called when the renderer puts a tab into or out of fullscreen mode.
   virtual void ToggleFullscreenModeForTab(WebContents* web_contents,
@@ -429,7 +429,7 @@ class CONTENT_EXPORT WebContentsDelegate {
   virtual bool RequestPpapiBrokerPermission(
       WebContents* web_contents,
       const GURL& url,
-      const FilePath& plugin_path,
+      const base::FilePath& plugin_path,
       const base::Callback<void(bool)>& callback);
 
  protected:
diff --git a/content/public/common/child_process_host.h b/content/public/common/child_process_host.h
index 9ded2978687baa..bccbd67b89d8d1 100644
--- a/content/public/common/child_process_host.h
+++ b/content/public/common/child_process_host.h
@@ -9,7 +9,9 @@
 #include "content/common/content_export.h"
 #include "ipc/ipc_channel_proxy.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 
@@ -71,7 +73,7 @@ class CONTENT_EXPORT ChildProcessHost : public IPC::Sender {
   // if none of these special behaviors are required.
   //
   // On failure, returns an empty FilePath.
-  static FilePath GetChildPath(int flags);
+  static base::FilePath GetChildPath(int flags);
 
   // Send the shutdown message to the child process.
   // Does not check with the delegate's CanShutdown.
diff --git a/content/public/common/sandbox_init.h b/content/public/common/sandbox_init.h
index 38224a2c940b67..de58f46432fd8e 100644
--- a/content/public/common/sandbox_init.h
+++ b/content/public/common/sandbox_init.h
@@ -11,7 +11,10 @@
 #include "ipc/ipc_platform_file.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace sandbox {
 struct SandboxInterfaceInfo;
@@ -54,7 +57,7 @@ CONTENT_EXPORT bool BrokerAddTargetPeer(HANDLE peer_process);
 // and returns a handle to it.
 CONTENT_EXPORT base::ProcessHandle StartProcessWithAccess(
     CommandLine* cmd_line,
-    const FilePath& exposed_dir);
+    const base::FilePath& exposed_dir);
 
 #elif defined(OS_MACOSX)
 
@@ -73,7 +76,7 @@ CONTENT_EXPORT base::ProcessHandle StartProcessWithAccess(
 // occurred.  If process_type isn't one that needs sandboxing, no action is
 // taken and true is always returned.
 CONTENT_EXPORT bool InitializeSandbox(int sandbox_type,
-                                      const FilePath& allowed_path);
+                                      const base::FilePath& allowed_path);
 
 #elif defined(OS_LINUX)
 
diff --git a/content/public/renderer/content_renderer_client.cc b/content/public/renderer/content_renderer_client.cc
index 84ea42cbf4bba9..595cad25abf010 100644
--- a/content/public/renderer/content_renderer_client.cc
+++ b/content/public/renderer/content_renderer_client.cc
@@ -28,7 +28,7 @@ bool ContentRendererClient::OverrideCreatePlugin(
 
 WebKit::WebPlugin* ContentRendererClient::CreatePluginReplacement(
     RenderView* render_view,
-    const FilePath& plugin_path) {
+    const base::FilePath& plugin_path) {
   return NULL;
 }
 
diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 80f215ca5cbca6..52dd68c1ae7a53 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -17,10 +17,13 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPageVisibilityState.h"
 #include "v8/include/v8.h"
 
-class FilePath;
 class GURL;
 class SkBitmap;
 
+namespace base {
+class FilePath;
+}
+
 namespace WebKit {
 class WebFrame;
 class WebMediaPlayerClient;
@@ -84,7 +87,7 @@ class CONTENT_EXPORT ContentRendererClient {
   // couldn't be loaded. This allows the embedder to show a custom placeholder.
   virtual WebKit::WebPlugin* CreatePluginReplacement(
       RenderView* render_view,
-      const FilePath& plugin_path);
+      const base::FilePath& plugin_path);
 
   // Returns true if the embedder has an error page to show for the given http
   // status code. If so |error_domain| should be set to according to WebURLError
diff --git a/content/public/renderer/renderer_ppapi_host.h b/content/public/renderer/renderer_ppapi_host.h
index da4a9b51a0de53..51a5e1fb6dbe47 100644
--- a/content/public/renderer/renderer_ppapi_host.h
+++ b/content/public/renderer/renderer_ppapi_host.h
@@ -13,7 +13,9 @@
 #include "ppapi/c/pp_instance.h"
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace gfx {
 class Point;
@@ -65,7 +67,7 @@ class RendererPpapiHost {
   CONTENT_EXPORT static RendererPpapiHost* CreateExternalPluginModule(
       scoped_refptr<webkit::ppapi::PluginModule> plugin_module,
       webkit::ppapi::PluginInstance* plugin_instance,
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       ppapi::PpapiPermissions permissions,
       const IPC::ChannelHandle& channel_handle,
       base::ProcessId plugin_pid,
diff --git a/content/public/test/browser_test_base.h b/content/public/test/browser_test_base.h
index 121b429469a236..026bf321f91001 100644
--- a/content/public/test/browser_test_base.h
+++ b/content/public/test/browser_test_base.h
@@ -10,7 +10,10 @@
 #include "net/test/test_server.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 namespace content {
 
@@ -77,7 +80,7 @@ class BrowserTestBase : public testing::Test {
   // this.
   // |test_server_base| is the path, relative to src, to give to the test HTTP
   // server.
-  void CreateTestServer(const FilePath& test_server_base);
+  void CreateTestServer(const base::FilePath& test_server_base);
 
  private:
   void ProxyRunTestOnMainThreadLoop();
diff --git a/content/public/test/test_launcher.h b/content/public/test/test_launcher.h
index 6a5e2a63ab96a1..d3404e5da3945e 100644
--- a/content/public/test/test_launcher.h
+++ b/content/public/test/test_launcher.h
@@ -11,9 +11,9 @@
 #include "base/compiler_specific.h"
 
 class CommandLine;
-class FilePath;
 
 namespace base {
+class FilePath;
 class RunLoop;
 }
 
@@ -39,8 +39,9 @@ class TestLauncherDelegate {
  public:
   virtual std::string GetEmptyTestName() = 0;
   virtual int RunTestSuite(int argc, char** argv) = 0;
-  virtual bool AdjustChildProcessCommandLine(CommandLine* command_line,
-                                             const FilePath& temp_data_dir) = 0;
+  virtual bool AdjustChildProcessCommandLine(
+      CommandLine* command_line,
+      const base::FilePath& temp_data_dir) = 0;
   virtual void PreRunMessageLoop(base::RunLoop* run_loop) {}
   virtual void PostRunMessageLoop() {}
   virtual ContentMainDelegate* CreateContentMainDelegate() = 0;
diff --git a/content/renderer/pepper/pepper_plugin_delegate_impl.h b/content/renderer/pepper/pepper_plugin_delegate_impl.h
index 8ced3eb53d4947..709b30bb50eadc 100644
--- a/content/renderer/pepper/pepper_plugin_delegate_impl.h
+++ b/content/renderer/pepper/pepper_plugin_delegate_impl.h
@@ -26,7 +26,9 @@
 #include "ui/base/ime/text_input_type.h"
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace IPC {
 struct ChannelHandle;
@@ -73,7 +75,7 @@ class PepperPluginDelegateImpl
   // module. Returns the renderer host, or NULL if it couldn't be created.
   RendererPpapiHost* CreateExternalPluginModule(
       scoped_refptr<webkit::ppapi::PluginModule> module,
-      const FilePath& path,
+      const base::FilePath& path,
       ppapi::PpapiPermissions permissions,
       const IPC::ChannelHandle& channel_handle,
       base::ProcessId plugin_pid,
@@ -167,7 +169,7 @@ class PepperPluginDelegateImpl
           webkit::ppapi::PluginInstance* instance) OVERRIDE;
   virtual SkBitmap* GetSadPluginBitmap() OVERRIDE;
   virtual WebKit::WebPlugin* CreatePluginReplacement(
-      const FilePath& file_path) OVERRIDE;
+      const base::FilePath& file_path) OVERRIDE;
   virtual uint32_t GetAudioHardwareOutputSampleRate() OVERRIDE;
   virtual uint32_t GetAudioHardwareOutputBufferSize() OVERRIDE;
   virtual PlatformAudioOutput* CreateAudioOutput(
@@ -197,7 +199,7 @@ class PepperPluginDelegateImpl
                                           int total,
                                           bool final_result) OVERRIDE;
   virtual void SelectedFindResultChanged(int identifier, int index) OVERRIDE;
-  virtual bool AsyncOpenFile(const FilePath& path,
+  virtual bool AsyncOpenFile(const base::FilePath& path,
                              int flags,
                              const AsyncOpenFileCallback& callback) OVERRIDE;
   virtual bool AsyncOpenFileSystemURL(
@@ -243,7 +245,7 @@ class PepperPluginDelegateImpl
   virtual void DidUpdateFile(const GURL& file_path, int64_t delta) OVERRIDE;
   virtual void SyncGetFileSystemPlatformPath(
       const GURL& url,
-      FilePath* platform_path) OVERRIDE;
+      base::FilePath* platform_path) OVERRIDE;
   virtual scoped_refptr<base::MessageLoopProxy>
       GetFileThreadMessageLoopProxy() OVERRIDE;
   virtual uint32 TCPSocketCreate() OVERRIDE;
@@ -381,7 +383,7 @@ class PepperPluginDelegateImpl
   // and perform other common initialization.
   RendererPpapiHost* CreateOutOfProcessModule(
       webkit::ppapi::PluginModule* module,
-      const FilePath& path,
+      const base::FilePath& path,
       ppapi::PpapiPermissions permissions,
       const IPC::ChannelHandle& channel_handle,
       base::ProcessId plugin_pid,
diff --git a/content/shell/shell_network_delegate.h b/content/shell/shell_network_delegate.h
index e1fb9915d1ed6d..12719617404c70 100644
--- a/content/shell/shell_network_delegate.h
+++ b/content/shell/shell_network_delegate.h
@@ -52,7 +52,7 @@ class ShellNetworkDelegate : public net::NetworkDelegate {
                               const std::string& cookie_line,
                               net::CookieOptions* options) OVERRIDE;
   virtual bool OnCanAccessFile(const net::URLRequest& request,
-                               const FilePath& path) const OVERRIDE;
+                               const base::FilePath& path) const OVERRIDE;
   virtual bool OnCanThrottleRequest(
       const net::URLRequest& request) const OVERRIDE;
   virtual int OnBeforeSocketStreamConnect(
diff --git a/content/test/content_browser_test_utils.h b/content/test/content_browser_test_utils.h
index 9ea40a5d542e7c..599c254f2c4213 100644
--- a/content/test/content_browser_test_utils.h
+++ b/content/test/content_browser_test_utils.h
@@ -9,7 +9,9 @@
 #include "googleurl/src/gurl.h"
 #include "ui/gfx/native_widget_types.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace gfx {
 class Rect;
@@ -28,7 +30,7 @@ class Shell;
 // The file for the tests is all located in
 // content/test/data/dir/<file>
 // The returned path is FilePath format.
-FilePath GetTestFilePath(const char* dir, const char* file);
+base::FilePath GetTestFilePath(const char* dir, const char* file);
 
 // Generate the URL for testing a particular test.
 // HTML for the tests is all located in
diff --git a/content/test/net/url_request_mock_http_job.h b/content/test/net/url_request_mock_http_job.h
index 9beb63adb151f1..53e69b51c554dc 100644
--- a/content/test/net/url_request_mock_http_job.h
+++ b/content/test/net/url_request_mock_http_job.h
@@ -12,7 +12,9 @@
 #include "net/url_request/url_request_file_job.h"
 #include "net/url_request/url_request_job_factory.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 
@@ -20,7 +22,7 @@ class URLRequestMockHTTPJob : public net::URLRequestFileJob {
  public:
   URLRequestMockHTTPJob(net::URLRequest* request,
                         net::NetworkDelegate* network_delegate,
-                        const FilePath& file_path);
+                        const base::FilePath& file_path);
 
   virtual bool GetMimeType(std::string* mime_type) const OVERRIDE;
   virtual int GetResponseCode() const OVERRIDE;
@@ -30,27 +32,27 @@ class URLRequestMockHTTPJob : public net::URLRequestFileJob {
                                   int* http_status_code) OVERRIDE;
 
   // Adds the testing URLs to the net::URLRequestFilter.
-  static void AddUrlHandler(const FilePath& base_path);
+  static void AddUrlHandler(const base::FilePath& base_path);
 
   // Respond to all HTTP requests of |hostname| with contents of the file
   // located at |file_path|.
   static void AddHostnameToFileHandler(const std::string& hostname,
-                                       const FilePath& file_path);
+                                       const base::FilePath& file_path);
 
   // Given the path to a file relative to the path passed to AddUrlHandler(),
   // construct a mock URL.
-  static GURL GetMockUrl(const FilePath& path);
+  static GURL GetMockUrl(const base::FilePath& path);
 
   // Given the path to a file relative to the path passed to AddUrlHandler(),
   // construct a mock URL for view source.
-  static GURL GetMockViewSourceUrl(const FilePath& path);
+  static GURL GetMockViewSourceUrl(const base::FilePath& path);
 
   // Returns a net::URLRequestJobFactory::ProtocolHandler that serves
   // URLRequestMockHTTPJob's responding like an HTTP server. |base_path| is the
   // file path leading to the root of the directory to use as the root of the
   // HTTP server.
   static scoped_ptr<net::URLRequestJobFactory::ProtocolHandler>
-  CreateProtocolHandler(const FilePath& base_path);
+  CreateProtocolHandler(const base::FilePath& base_path);
 
  private:
   virtual ~URLRequestMockHTTPJob();
diff --git a/content/test/net/url_request_prepackaged_interceptor.h b/content/test/net/url_request_prepackaged_interceptor.h
index 88b2291039bb91..edb65c585597eb 100644
--- a/content/test/net/url_request_prepackaged_interceptor.h
+++ b/content/test/net/url_request_prepackaged_interceptor.h
@@ -7,9 +7,12 @@
 
 #include "base/basictypes.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace content {
 
 // Intercepts HTTP requests and gives pre-defined responses to specified URLs.
@@ -23,11 +26,11 @@ class URLRequestPrepackagedInterceptor {
   // When requests for |url| arrive, respond with the contents of |path|. The
   // hostname of |url| must be "localhost" to avoid DNS lookups, and the scheme
   // must be "http".
-  void SetResponse(const GURL& url, const FilePath& path);
+  void SetResponse(const GURL& url, const base::FilePath& path);
 
   // Identical to SetResponse except that query parameters are ignored on
   // incoming URLs when comparing against |url|.
-  void SetResponseIgnoreQuery(const GURL& url, const FilePath& path);
+  void SetResponseIgnoreQuery(const GURL& url, const base::FilePath& path);
 
   // Returns how many requests have been issued that have a stored reply.
   int GetHitCount();
diff --git a/content/utility/utility_thread_impl.h b/content/utility/utility_thread_impl.h
index 12c76de80e0e27..da2ffbd1db0fb2 100644
--- a/content/utility/utility_thread_impl.h
+++ b/content/utility/utility_thread_impl.h
@@ -14,7 +14,9 @@
 #include "content/common/content_export.h"
 #include "content/public/utility/utility_thread.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace content {
 class WebKitPlatformSupportImpl;
@@ -42,7 +44,7 @@ class UtilityThreadImpl : public UtilityThread,
   void OnBatchModeFinished();
 
 #if defined(OS_POSIX)
-  void OnLoadPlugins(const std::vector<FilePath>& plugin_paths);
+  void OnLoadPlugins(const std::vector<base::FilePath>& plugin_paths);
 #endif  // OS_POSIX
 
   // True when we're running in batch mode.
diff --git a/crypto/nss_util.h b/crypto/nss_util.h
index 7b50781d036eee..60b77783e22061 100644
--- a/crypto/nss_util.h
+++ b/crypto/nss_util.h
@@ -9,11 +9,8 @@
 #include "base/basictypes.h"
 #include "crypto/crypto_export.h"
 
-#if defined(USE_NSS)
-class FilePath;
-#endif  // defined(USE_NSS)
-
 namespace base {
+class FilePath;
 class Lock;
 class Time;
 }  // namespace base
diff --git a/gpu/tools/compositor_model_bench/render_tree.h b/gpu/tools/compositor_model_bench/render_tree.h
index 5ac01e5072ce85..adee4b81811713 100644
--- a/gpu/tools/compositor_model_bench/render_tree.h
+++ b/gpu/tools/compositor_model_bench/render_tree.h
@@ -205,7 +205,7 @@ class RenderNodeVisitor {
   virtual void EndVisitCCNode(CCNode* v);
 };
 
-RenderNode* BuildRenderTreeFromFile(const FilePath& path);
+RenderNode* BuildRenderTreeFromFile(const base::FilePath& path);
 
 #endif  // GPU_TOOLS_COMPOSITOR_MODEL_BENCH_RENDER_TREE_H_
 
diff --git a/ipc/ipc_message_utils.h b/ipc/ipc_message_utils.h
index 73006598617b7c..fc72210059e2f9 100644
--- a/ipc/ipc_message_utils.h
+++ b/ipc/ipc_message_utils.h
@@ -45,11 +45,11 @@
 #error "Please add the noinline property for your new compiler here."
 #endif
 
-class FilePath;
 class NullableString16;
 
 namespace base {
 class DictionaryValue;
+class FilePath;
 class ListValue;
 class Time;
 class TimeDelta;
@@ -438,8 +438,8 @@ struct IPC_EXPORT ParamTraits<base::FileDescriptor> {
 #endif  // defined(OS_POSIX)
 
 template <>
-struct IPC_EXPORT ParamTraits<FilePath> {
-  typedef FilePath param_type;
+struct IPC_EXPORT ParamTraits<base::FilePath> {
+  typedef base::FilePath param_type;
   static void Write(Message* m, const param_type& p);
   static bool Read(const Message* m, PickleIterator* iter, param_type* r);
   static void Log(const param_type& p, std::string* l);
diff --git a/media/base/media.h b/media/base/media.h
index 277c740e783cf1..55189610fb2be5 100644
--- a/media/base/media.h
+++ b/media/base/media.h
@@ -10,7 +10,9 @@
 
 #include "media/base/media_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace media {
 
@@ -25,7 +27,7 @@ namespace media {
 // of the process.
 //
 // Returns true if everything was successfully initialized, false otherwise.
-MEDIA_EXPORT bool InitializeMediaLibrary(const FilePath& module_dir);
+MEDIA_EXPORT bool InitializeMediaLibrary(const base::FilePath& module_dir);
 
 // Helper function for unit tests to avoid boiler plate code everywhere. This
 // function will crash if it fails to load the media library. This ensures tests
diff --git a/media/base/media_stub.cc b/media/base/media_stub.cc
index a42bbf9dd7d0a0..27bdc15e2d6be0 100644
--- a/media/base/media_stub.cc
+++ b/media/base/media_stub.cc
@@ -10,7 +10,7 @@
 // libraries (e.g., Android and iOS).
 namespace media {
 
-bool InitializeMediaLibrary(const FilePath& module_dir) {
+bool InitializeMediaLibrary(const base::FilePath& module_dir) {
   return true;
 }
 
diff --git a/media/filters/pipeline_integration_test_base.h b/media/filters/pipeline_integration_test_base.h
index dedbb70c57a9c5..19bdda0fa30b33 100644
--- a/media/filters/pipeline_integration_test_base.h
+++ b/media/filters/pipeline_integration_test_base.h
@@ -14,7 +14,9 @@
 #include "media/filters/video_renderer_base.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace media {
 
@@ -39,14 +41,14 @@ class PipelineIntegrationTestBase {
 
   bool WaitUntilOnEnded();
   PipelineStatus WaitUntilEndedOrError();
-  bool Start(const FilePath& file_path, PipelineStatus expected_status);
+  bool Start(const base::FilePath& file_path, PipelineStatus expected_status);
   // Enable playback with audio and video hashing enabled.  Frame dropping and
   // audio underflow will be disabled to ensure consistent hashes.
-  bool Start(const FilePath& file_path, PipelineStatus expected_status,
+  bool Start(const base::FilePath& file_path, PipelineStatus expected_status,
              bool hashing_enabled);
   // Initialize the pipeline and ignore any status updates.  Useful for testing
   // invalid audio/video clips which don't have deterministic results.
-  bool Start(const FilePath& file_path);
+  bool Start(const base::FilePath& file_path);
 
   void Play();
   void Pause();
@@ -54,7 +56,7 @@ class PipelineIntegrationTestBase {
   void Stop();
   bool WaitUntilCurrentTimeIsAfter(const base::TimeDelta& wait_time);
   scoped_ptr<FilterCollection> CreateFilterCollection(
-      const FilePath& file_path);
+      const base::FilePath& file_path);
 
   // Returns the MD5 hash of all video frames seen.  Should only be called once
   // after playback completes.  First time hashes should be generated with
diff --git a/media/webm/chromeos/webm_encoder.h b/media/webm/chromeos/webm_encoder.h
index d0e74143aa714b..cced7320585cc9 100644
--- a/media/webm/chromeos/webm_encoder.h
+++ b/media/webm/chromeos/webm_encoder.h
@@ -18,9 +18,12 @@ extern "C" {
 #include "third_party/libvpx/source/libvpx/vpx/vp8cx.h"
 }
 
-class FilePath;
 class SkBitmap;
 
+namespace base {
+class FilePath;
+}
+
 namespace media {
 
 namespace chromeos {
@@ -33,7 +36,7 @@ class MEDIA_EXPORT WebmEncoder {
  public:
   // Create new instance for writing to |output_path|. If |realtime| is |true|,
   // uses realtime deadline, otherwise - "good quality" deadline.
-  WebmEncoder(const FilePath& output_path, int bitrate, bool realtime);
+  WebmEncoder(const base::FilePath& output_path, int bitrate, bool realtime);
   ~WebmEncoder();
 
   // Encodes video from a Nx(N*M) sprite, having M frames of size NxN with FPS
@@ -87,7 +90,7 @@ class MEDIA_EXPORT WebmEncoder {
   // Stack with start offsets of currently open sub-elements.
   std::stack<long int> ebml_sub_elements_;
 
-  FilePath output_path_;
+  base::FilePath output_path_;
   FILE* output_;
 
   // True if an error occured while encoding/writing to file.
diff --git a/net/base/cert_test_util.h b/net/base/cert_test_util.h
index 9f23b7debf1dbb..db49e87327c8ea 100644
--- a/net/base/cert_test_util.h
+++ b/net/base/cert_test_util.h
@@ -11,13 +11,15 @@
 #include "net/base/x509_cert_types.h"
 #include "net/base/x509_certificate.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace net {
 
 class EVRootCAMetadata;
 
-CertificateList CreateCertificateListFromFile(const FilePath& certs_dir,
+CertificateList CreateCertificateListFromFile(const base::FilePath& certs_dir,
                                               const std::string& cert_file,
                                               int format);
 
@@ -26,7 +28,7 @@ CertificateList CreateCertificateListFromFile(const FilePath& certs_dir,
 // |certs_dir| represents the test certificates directory. |cert_file| is the
 // name of the certificate file. If cert_file contains multiple certificates,
 // the first certificate found will be returned.
-scoped_refptr<X509Certificate> ImportCertFromFile(const FilePath& certs_dir,
+scoped_refptr<X509Certificate> ImportCertFromFile(const base::FilePath& certs_dir,
                                                   const std::string& cert_file);
 
 // ScopedTestEVPolicy causes certificates marked with |policy|, issued from a
diff --git a/net/base/file_stream.h b/net/base/file_stream.h
index 5c6479238a2033..763a03cb528453 100644
--- a/net/base/file_stream.h
+++ b/net/base/file_stream.h
@@ -16,7 +16,9 @@
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace net {
 
@@ -54,7 +56,7 @@ class NET_EXPORT FileStream {
   // automatically closed when FileStream is destructed in an asynchronous
   // manner (i.e. the file stream is closed in the background but you don't
   // know when).
-  virtual int Open(const FilePath& path, int open_flags,
+  virtual int Open(const base::FilePath& path, int open_flags,
                    const CompletionCallback& callback);
 
   // Call this method to open the FileStream synchronously.
@@ -64,7 +66,7 @@ class NET_EXPORT FileStream {
   //
   // If the file stream is not closed manually, the underlying file will be
   // automatically closed when FileStream is destructed.
-  virtual int OpenSync(const FilePath& path, int open_flags);
+  virtual int OpenSync(const base::FilePath& path, int open_flags);
 
   // Returns true if Open succeeded and Close has not been called.
   virtual bool IsOpen() const;
diff --git a/net/base/file_stream_context.h b/net/base/file_stream_context.h
index 244c25f4c40d97..42fc0eb573c914 100644
--- a/net/base/file_stream_context.h
+++ b/net/base/file_stream_context.h
@@ -39,7 +39,9 @@
 #include <errno.h>
 #endif
 
+namespace base {
 class FilePath;
+}
 
 namespace net {
 
@@ -97,10 +99,10 @@ class FileStream::Context {
   // not closed yet.
   void Orphan();
 
-  void OpenAsync(const FilePath& path,
+  void OpenAsync(const base::FilePath& path,
                  int open_flags,
                  const CompletionCallback& callback);
-  int OpenSync(const FilePath& path, int open_flags);
+  int OpenSync(const base::FilePath& path, int open_flags);
 
   void CloseSync();
 
@@ -137,9 +139,9 @@ class FileStream::Context {
   // Map system error into network error code and log it with |bound_net_log_|.
   int RecordAndMapError(int error, FileErrorSource source) const;
 
-  void BeginOpenEvent(const FilePath& path);
+  void BeginOpenEvent(const base::FilePath& path);
 
-  OpenResult OpenFileImpl(const FilePath& path, int open_flags);
+  OpenResult OpenFileImpl(const base::FilePath& path, int open_flags);
 
   int ProcessOpenError(int error_code);
   void OnOpenCompleted(const CompletionCallback& callback, OpenResult result);
diff --git a/net/base/net_util.h b/net/base/net_util.h
index 874f3e20308a27..f21c1edb16ce24 100644
--- a/net/base/net_util.h
+++ b/net/base/net_util.h
@@ -26,10 +26,10 @@
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -79,13 +79,13 @@ NET_EXPORT_PRIVATE extern size_t GetCountOfExplicitlyAllowedPorts();
 
 // Given the full path to a file name, creates a file: URL. The returned URL
 // may not be valid if the input is malformed.
-NET_EXPORT GURL FilePathToFileURL(const FilePath& path);
+NET_EXPORT GURL FilePathToFileURL(const base::FilePath& path);
 
 // Converts a file: URL back to a filename that can be passed to the OS. The
 // file URL must be well-formed (GURL::is_valid() must return true); we don't
 // handle degenerate cases here. Returns true on success, false if it isn't a
 // valid file URL. On failure, *file_path will be empty.
-NET_EXPORT bool FileURLToFilePath(const GURL& url, FilePath* file_path);
+NET_EXPORT bool FileURLToFilePath(const GURL& url, base::FilePath* file_path);
 
 // Splits an input of the form <host>[":"<port>] into its consitituent parts.
 // Saves the result into |*host| and |*port|. If the input did not have
@@ -278,12 +278,13 @@ NET_EXPORT string16 GetSuggestedFilename(const GURL& url,
                                          const std::string& default_name);
 
 // Similar to GetSuggestedFilename(), but returns a FilePath.
-NET_EXPORT FilePath GenerateFileName(const GURL& url,
-                                     const std::string& content_disposition,
-                                     const std::string& referrer_charset,
-                                     const std::string& suggested_name,
-                                     const std::string& mime_type,
-                                     const std::string& default_name);
+NET_EXPORT base::FilePath GenerateFileName(
+    const GURL& url,
+    const std::string& content_disposition,
+    const std::string& referrer_charset,
+    const std::string& suggested_name,
+    const std::string& mime_type,
+    const std::string& default_name);
 
 // Ensures that the filename and extension is safe to use in the filesystem.
 //
@@ -304,7 +305,7 @@ NET_EXPORT FilePath GenerateFileName(const GURL& url,
 // thread that allows IO.
 NET_EXPORT void GenerateSafeFileName(const std::string& mime_type,
                                      bool ignore_extension,
-                                     FilePath* file_path);
+                                     base::FilePath* file_path);
 
 // Checks |port| against a list of ports which are restricted by default.
 // Returns true if |port| is allowed, false if it is restricted.
diff --git a/net/base/network_delegate.cc b/net/base/network_delegate.cc
index 539d9877530f3f..59953a8dde0ff6 100644
--- a/net/base/network_delegate.cc
+++ b/net/base/network_delegate.cc
@@ -108,7 +108,7 @@ bool NetworkDelegate::CanGetCookies(const URLRequest& request,
 }
 
 bool NetworkDelegate::CanAccessFile(const URLRequest& request,
-                                    const FilePath& path) const {
+                                    const base::FilePath& path) const {
   DCHECK(CalledOnValidThread());
   return OnCanAccessFile(request, path);
 }
diff --git a/net/base/network_delegate.h b/net/base/network_delegate.h
index 5475754fa37417..f2198540f40ddc 100644
--- a/net/base/network_delegate.h
+++ b/net/base/network_delegate.h
@@ -14,9 +14,12 @@
 #include "net/base/completion_callback.h"
 #include "net/cookies/canonical_cookie.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace net {
 
 // NOTE: Layering violations!
@@ -92,7 +95,7 @@ class NET_EXPORT NetworkDelegate : public base::NonThreadSafe {
                     const std::string& cookie_line,
                     CookieOptions* options);
   bool CanAccessFile(const URLRequest& request,
-                     const FilePath& path) const;
+                     const base::FilePath& path) const;
   bool CanThrottleRequest(const URLRequest& request) const;
 
   int NotifyBeforeSocketStreamConnect(SocketStream* socket,
@@ -215,7 +218,7 @@ class NET_EXPORT NetworkDelegate : public base::NonThreadSafe {
   // allow or block access to the given file path.  Returns true if access is
   // allowed.
   virtual bool OnCanAccessFile(const URLRequest& request,
-                               const FilePath& path) const = 0;
+                               const base::FilePath& path) const = 0;
 
   // Returns true if the given request may be rejected when the
   // URLRequestThrottlerManager believes the server servicing the
diff --git a/net/base/test_root_certs.h b/net/base/test_root_certs.h
index 4d52dbcda5c088..a7c7cdeb548249 100644
--- a/net/base/test_root_certs.h
+++ b/net/base/test_root_certs.h
@@ -21,7 +21,9 @@
 #include "base/mac/scoped_cftyperef.h"
 #endif
 
+namespace base {
 class FilePath;
+}
 
 namespace net {
 
@@ -45,7 +47,7 @@ class NET_EXPORT_PRIVATE TestRootCerts {
   // Reads a single certificate from |file| and marks it as trusted. Returns
   // false if an error is encountered, such as being unable to read |file|
   // or more than one certificate existing in |file|.
-  bool AddFromFile(const FilePath& file);
+  bool AddFromFile(const base::FilePath& file);
 
   // Clears the trusted status of any certificates that were previously
   // marked trusted via Add().
diff --git a/net/base/upload_data.h b/net/base/upload_data.h
index 4e6c6ca3c413e4..b782ab4e4ded7e 100644
--- a/net/base/upload_data.h
+++ b/net/base/upload_data.h
@@ -12,9 +12,8 @@
 #include "net/base/net_export.h"
 #include "net/base/upload_element.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class Time;
 }  // namespace base
 
@@ -35,7 +34,7 @@ class NET_EXPORT UploadData
 
   void AppendBytes(const char* bytes, int bytes_len);
 
-  void AppendFileRange(const FilePath& file_path,
+  void AppendFileRange(const base::FilePath& file_path,
                        uint64 offset, uint64 length,
                        const base::Time& expected_modification_time);
 
diff --git a/net/disk_cache/cache_util.h b/net/disk_cache/cache_util.h
index 6987dc38a8e982..0b3ee6e0255f44 100644
--- a/net/disk_cache/cache_util.h
+++ b/net/disk_cache/cache_util.h
@@ -8,7 +8,9 @@
 #include "base/basictypes.h"
 #include "net/base/net_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace disk_cache {
 
@@ -18,15 +20,16 @@ namespace disk_cache {
 // for the cache directory.  Returns true if successful.  On ChromeOS,
 // this moves the cache contents, and leaves the empty cache
 // directory.
-NET_EXPORT_PRIVATE bool MoveCache(const FilePath& from_path,
-                                  const FilePath& to_path);
+NET_EXPORT_PRIVATE bool MoveCache(const base::FilePath& from_path,
+                                  const base::FilePath& to_path);
 
 // Deletes the cache files stored on |path|, and optionally also attempts to
 // delete the folder itself.
-NET_EXPORT_PRIVATE void DeleteCache(const FilePath& path, bool remove_folder);
+NET_EXPORT_PRIVATE void DeleteCache(const base::FilePath& path,
+                                    bool remove_folder);
 
 // Deletes a cache file.
-NET_EXPORT_PRIVATE bool DeleteCacheFile(const FilePath& name);
+NET_EXPORT_PRIVATE bool DeleteCacheFile(const base::FilePath& name);
 
 }  // namespace disk_cache
 
diff --git a/net/disk_cache/disk_cache.h b/net/disk_cache/disk_cache.h
index d2e01a01ffb0f4..e27d24ce4a5d15 100644
--- a/net/disk_cache/disk_cache.h
+++ b/net/disk_cache/disk_cache.h
@@ -17,9 +17,8 @@
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class MessageLoopProxy;
 }
 
@@ -48,7 +47,8 @@ class Backend;
 // be invoked when a backend is available or a fatal error condition is reached.
 // The pointer to receive the |backend| must remain valid until the operation
 // completes (the callback is notified).
-NET_EXPORT int CreateCacheBackend(net::CacheType type, const FilePath& path,
+NET_EXPORT int CreateCacheBackend(net::CacheType type,
+                                  const base::FilePath& path,
                                   int max_bytes, bool force,
                                   base::MessageLoopProxy* thread,
                                   net::NetLog* net_log, Backend** backend,
diff --git a/net/disk_cache/file.h b/net/disk_cache/file.h
index 0124090f434bb3..3f17ea0085f387 100644
--- a/net/disk_cache/file.h
+++ b/net/disk_cache/file.h
@@ -11,7 +11,9 @@
 #include "base/platform_file.h"
 #include "net/base/net_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace disk_cache {
 
diff --git a/net/disk_cache/mapped_file.h b/net/disk_cache/mapped_file.h
index c5960d0c6ba165..61909975422de6 100644
--- a/net/disk_cache/mapped_file.h
+++ b/net/disk_cache/mapped_file.h
@@ -12,7 +12,9 @@
 #include "net/disk_cache/file.h"
 #include "net/disk_cache/file_block.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace disk_cache {
 
@@ -27,7 +29,7 @@ class NET_EXPORT_PRIVATE MappedFile : public File {
   // Performs object initialization. name is the file to use, and size is the
   // amount of data to memory map from the file. If size is 0, the whole file
   // will be mapped in memory.
-  void* Init(const FilePath& name, size_t size);
+  void* Init(const base::FilePath& name, size_t size);
 
   void* buffer() const {
     return buffer_;
diff --git a/net/http/infinite_cache.h b/net/http/infinite_cache.h
index 30d90257cd594e..a93d4c15cd033f 100644
--- a/net/http/infinite_cache.h
+++ b/net/http/infinite_cache.h
@@ -18,9 +18,8 @@
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 class SequencedWorkerPool;
 }
@@ -80,7 +79,7 @@ class NET_EXPORT_PRIVATE InfiniteCache
   // Initializes this object to start tracking requests. |path| is the location
   // of the file to use to store data; it can be empty, in which case the data
   // will not be persisted to disk.
-  void Init(const FilePath& path);
+  void Init(const base::FilePath& path);
 
   InfiniteCacheTransaction* CreateInfiniteCacheTransaction();
 
diff --git a/net/test/python_utils.h b/net/test/python_utils.h
index c7cf289310703c..30776456503f7b 100644
--- a/net/test/python_utils.h
+++ b/net/test/python_utils.h
@@ -8,16 +8,19 @@
 #include "base/compiler_specific.h"
 
 class CommandLine;
+
+namespace base {
 class FilePath;
+}
 
 // This is the python path variable name.
 extern const char kPythonPathEnv[];
 
 // Appends the dir to python path environment variable.
-void AppendToPythonPath(const FilePath& dir);
+void AppendToPythonPath(const base::FilePath& dir);
 
 // Return the location of the compiler-generated python protobuf.
-bool GetPyProtoPath(FilePath* dir);
+bool GetPyProtoPath(base::FilePath* dir);
 
 // Returns the command that should be used to launch Python.
 bool GetPythonCommand(CommandLine* python_cmd) WARN_UNUSED_RESULT;
diff --git a/net/url_request/url_fetcher.h b/net/url_request/url_fetcher.h
index 815dac088d3602..fdd436749dc560 100644
--- a/net/url_request/url_fetcher.h
+++ b/net/url_request/url_fetcher.h
@@ -16,10 +16,10 @@
 #include "base/task_runner.h"
 #include "net/base/net_export.h"
 
-class FilePath;
 class GURL;
 
 namespace base {
+class FilePath;
 class MessageLoopProxy;
 class TimeDelta;
 }
@@ -220,7 +220,7 @@ class NET_EXPORT URLFetcher {
   // The created file is removed when the URLFetcher is deleted unless you
   // take ownership by calling GetResponseAsFilePath().
   virtual void SaveResponseToFileAtPath(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       scoped_refptr<base::TaskRunner> file_task_runner) = 0;
 
   // By default, the response is saved in a string. Call this method to save the
@@ -284,7 +284,7 @@ class NET_EXPORT URLFetcher {
   // be removed once the URLFetcher is destroyed.  User should not take
   // ownership more than once, or call this method after taking ownership.
   virtual bool GetResponseAsFilePath(bool take_ownership,
-                                     FilePath* out_response_path) const = 0;
+                                     base::FilePath* out_response_path) const = 0;
 };
 
 }  // namespace net
diff --git a/net/url_request/url_request.h b/net/url_request/url_request.h
index a0ed0b205054d9..3c1c2d522e44ff 100644
--- a/net/url_request/url_request.h
+++ b/net/url_request/url_request.h
@@ -30,7 +30,6 @@
 #include "net/http/http_response_info.h"
 #include "net/url_request/url_request_status.h"
 
-class FilePath;
 // Temporary layering violation to allow existing users of a deprecated
 // interface.
 class ChildProcessSecurityPolicyTest;
diff --git a/net/url_request/url_request_context_builder.h b/net/url_request/url_request_context_builder.h
index fd21f8a62fe3a5..f1ce5707a66866 100644
--- a/net/url_request/url_request_context_builder.h
+++ b/net/url_request/url_request_context_builder.h
@@ -49,7 +49,7 @@ class NET_EXPORT URLRequestContextBuilder {
     int max_size;
 
     // The cache path (when type is DISK).
-    FilePath path;
+    base::FilePath path;
   };
 
   struct NET_EXPORT HttpNetworkSessionParams {
diff --git a/printing/emf_win.h b/printing/emf_win.h
index 2f0772f3f80334..3516f4efb7d185 100644
--- a/printing/emf_win.h
+++ b/printing/emf_win.h
@@ -14,7 +14,9 @@
 #include "base/gtest_prod_util.h"
 #include "printing/metafile.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace gfx {
 class Rect;
@@ -42,10 +44,10 @@ class PRINTING_EXPORT Emf : public Metafile {
 
   // Generates a new metafile that will record every GDI command, and will
   // be saved to |metafile_path|.
-  virtual bool InitToFile(const FilePath& metafile_path);
+  virtual bool InitToFile(const base::FilePath& metafile_path);
 
   // Initializes the Emf with the data in |metafile_path|.
-  virtual bool InitFromFile(const FilePath& metafile_path);
+  virtual bool InitFromFile(const base::FilePath& metafile_path);
 
   // Metafile methods.
   virtual bool Init() OVERRIDE;
@@ -71,7 +73,7 @@ class PRINTING_EXPORT Emf : public Metafile {
   // Saves the EMF data to a file as-is. It is recommended to use the .emf file
   // extension but it is not enforced. This function synchronously writes to the
   // file. For testing only.
-  virtual bool SaveTo(const FilePath& file_path) const OVERRIDE;
+  virtual bool SaveTo(const base::FilePath& file_path) const OVERRIDE;
 
   // Should be passed to Playback to keep the exact same size.
   virtual gfx::Rect GetPageBounds(unsigned int page_number) const OVERRIDE;
diff --git a/printing/image.h b/printing/image.h
index e34c2c24c501a9..b40657a3782dda 100644
--- a/printing/image.h
+++ b/printing/image.h
@@ -13,7 +13,9 @@
 #include "printing/printing_export.h"
 #include "ui/gfx/size.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace printing {
 
@@ -26,7 +28,7 @@ class PRINTING_EXPORT Image {
   // Creates the image from the given file on disk.  Uses extension to
   // defer file type. PNG and EMF (on Windows) currently supported.
   // If image loading fails size().IsEmpty() will be true.
-  explicit Image(const FilePath& path);
+  explicit Image(const base::FilePath& path);
 
   // Creates the image from the metafile.  Deduces bounds based on bounds in
   // metafile.  If loading fails size().IsEmpty() will be true.
@@ -45,7 +47,7 @@ class PRINTING_EXPORT Image {
   std::string checksum() const;
 
   // Save image as PNG.
-  bool SaveToPng(const FilePath& filepath) const;
+  bool SaveToPng(const base::FilePath& filepath) const;
 
   // Returns % of pixels different
   double PercentageDifferent(const Image& rhs) const;
diff --git a/printing/metafile.h b/printing/metafile.h
index a73c850ccf024e..ca0901b2b65c00 100644
--- a/printing/metafile.h
+++ b/printing/metafile.h
@@ -18,7 +18,9 @@
 #include "base/mac/scoped_cftyperef.h"
 #endif
 
+namespace base {
 class FilePath;
+}
 
 namespace gfx {
 class Rect;
@@ -117,7 +119,7 @@ class PRINTING_EXPORT Metafile {
 
   // Saves the underlying data to the given file. This function should ONLY be
   // called after the metafile is closed. Returns true if writing succeeded.
-  virtual bool SaveTo(const FilePath& file_path) const = 0;
+  virtual bool SaveTo(const base::FilePath& file_path) const = 0;
 
   // Returns the bounds of the given page. Pages use a 1-based index.
   virtual gfx::Rect GetPageBounds(unsigned int page_number) const = 0;
diff --git a/printing/pdf_metafile_cg_mac.h b/printing/pdf_metafile_cg_mac.h
index 09fad566790276..f4dd81acf8166f 100644
--- a/printing/pdf_metafile_cg_mac.h
+++ b/printing/pdf_metafile_cg_mac.h
@@ -14,7 +14,9 @@
 #include "base/threading/thread_checker.h"
 #include "printing/metafile.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace gfx {
 class Rect;
@@ -48,7 +50,7 @@ class PRINTING_EXPORT PdfMetafileCg : public Metafile {
   virtual bool GetData(void* dst_buffer, uint32 dst_buffer_size) const OVERRIDE;
 
   // For testing purposes only.
-  virtual bool SaveTo(const FilePath& file_path) const OVERRIDE;
+  virtual bool SaveTo(const base::FilePath& file_path) const OVERRIDE;
 
   virtual gfx::Rect GetPageBounds(unsigned int page_number) const OVERRIDE;
   virtual unsigned int GetPageCount() const OVERRIDE;
diff --git a/printing/pdf_metafile_skia.h b/printing/pdf_metafile_skia.h
index 7a1a9da66119df..33be6d2e0f47c3 100644
--- a/printing/pdf_metafile_skia.h
+++ b/printing/pdf_metafile_skia.h
@@ -44,7 +44,7 @@ class PRINTING_EXPORT PdfMetafileSkia : public Metafile {
   virtual uint32 GetDataSize() const OVERRIDE;
   virtual bool GetData(void* dst_buffer, uint32 dst_buffer_size) const OVERRIDE;
 
-  virtual bool SaveTo(const FilePath& file_path) const OVERRIDE;
+  virtual bool SaveTo(const base::FilePath& file_path) const OVERRIDE;
 
   virtual gfx::Rect GetPageBounds(unsigned int page_number) const OVERRIDE;
   virtual unsigned int GetPageCount() const OVERRIDE;
diff --git a/printing/printed_document.h b/printing/printed_document.h
index bdb092fc3223d6..3992386c294561 100644
--- a/printing/printed_document.h
+++ b/printing/printed_document.h
@@ -13,9 +13,12 @@
 #include "printing/print_settings.h"
 #include "ui/gfx/native_widget_types.h"
 
-class FilePath;
 class MessageLoop;
 
+namespace base {
+class FilePath;
+}
+
 namespace printing {
 
 class Metafile;
@@ -93,9 +96,9 @@ class PRINTING_EXPORT PrintedDocument
 
   // Sets a path where to dump printing output files for debugging. If never set
   // no files are generated.
-  static void set_debug_dump_path(const FilePath& debug_dump_path);
+  static void set_debug_dump_path(const base::FilePath& debug_dump_path);
 
-  static const FilePath& debug_dump_path();
+  static const base::FilePath& debug_dump_path();
 
  private:
   friend class base::RefCountedThreadSafe<PrintedDocument>;
diff --git a/remoting/host/audio_capturer_linux.cc b/remoting/host/audio_capturer_linux.cc
index 59e30e41445660..3dd6d6822591e5 100644
--- a/remoting/host/audio_capturer_linux.cc
+++ b/remoting/host/audio_capturer_linux.cc
@@ -27,7 +27,7 @@ base::LazyInstance<scoped_refptr<AudioPipeReader> >::Leaky
 // See crbug.com/161373 and crbug.com/104544.
 void AudioCapturerLinux::InitializePipeReader(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    const FilePath& pipe_name) {
+    const base::FilePath& pipe_name) {
   scoped_refptr<AudioPipeReader> pipe_reader;
   if (!pipe_name.empty())
     pipe_reader = AudioPipeReader::Create(task_runner, pipe_name);
diff --git a/remoting/host/audio_capturer_linux.h b/remoting/host/audio_capturer_linux.h
index b52f1ff9e57ec1..466ccf6cd4d826 100644
--- a/remoting/host/audio_capturer_linux.h
+++ b/remoting/host/audio_capturer_linux.h
@@ -10,7 +10,9 @@
 #include "remoting/host/audio_silence_detector.h"
 #include "remoting/host/linux/audio_pipe_reader.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace remoting {
 
@@ -24,7 +26,7 @@ class AudioCapturerLinux : public AudioCapturer,
   // to read from the pipe.
   static void InitializePipeReader(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-      const FilePath& pipe_name);
+      const base::FilePath& pipe_name);
 
   explicit AudioCapturerLinux(
       scoped_refptr<AudioPipeReader> pipe_reader);
diff --git a/remoting/host/branding.cc b/remoting/host/branding.cc
index c0498546e915cc..908d9bc96689a8 100644
--- a/remoting/host/branding.cc
+++ b/remoting/host/branding.cc
@@ -16,17 +16,17 @@ namespace {
 // command-line switches are absent.
 #if defined(OS_WIN)
 #ifdef OFFICIAL_BUILD
-const FilePath::CharType kConfigDir[] =
+const base::FilePath::CharType kConfigDir[] =
     FILE_PATH_LITERAL("Google\\Chrome Remote Desktop");
 #else
-const FilePath::CharType kConfigDir[] =
+const base::FilePath::CharType kConfigDir[] =
     FILE_PATH_LITERAL("Chromoting");
 #endif
 #elif defined(OS_MACOSX)
-const FilePath::CharType kConfigDir[] =
+const base::FilePath::CharType kConfigDir[] =
     FILE_PATH_LITERAL("Chrome Remote Desktop");
 #else
-const FilePath::CharType kConfigDir[] =
+const base::FilePath::CharType kConfigDir[] =
     FILE_PATH_LITERAL(".config/chrome-remote-desktop");
 #endif
 
@@ -38,8 +38,8 @@ namespace remoting {
 const wchar_t kWindowsServiceName[] = L"chromoting";
 #endif
 
-FilePath GetConfigDir() {
-  FilePath app_data_dir;
+base::FilePath GetConfigDir() {
+  base::FilePath app_data_dir;
 
 #if defined(OS_WIN)
   PathService::Get(base::DIR_COMMON_APP_DATA, &app_data_dir);
diff --git a/remoting/host/branding.h b/remoting/host/branding.h
index c139fb414b4a12..a076bda24131fe 100644
--- a/remoting/host/branding.h
+++ b/remoting/host/branding.h
@@ -15,7 +15,7 @@ extern const wchar_t kWindowsServiceName[];
 #endif
 
 // Returns the location of the host configuration directory.
-FilePath GetConfigDir();
+base::FilePath GetConfigDir();
 
 } // namespace remoting
 
diff --git a/remoting/host/config_file_watcher.cc b/remoting/host/config_file_watcher.cc
index 4e6b77ab0fa35d..085046078416df 100644
--- a/remoting/host/config_file_watcher.cc
+++ b/remoting/host/config_file_watcher.cc
@@ -21,7 +21,7 @@ namespace remoting {
 // file to use.
 const char kHostConfigSwitchName[] = "host-config";
 
-const FilePath::CharType kDefaultHostConfigFile[] =
+const base::FilePath::CharType kDefaultHostConfigFile[] =
     FILE_PATH_LITERAL("host.json");
 
 class ConfigFileWatcherImpl
@@ -35,7 +35,7 @@ class ConfigFileWatcherImpl
       ConfigFileWatcher::Delegate* delegate);
 
   // Starts watching |config_path|.
-  void Watch(const FilePath& config_path);
+  void Watch(const base::FilePath& config_path);
 
   // Stops watching the configuration file.
   void StopWatching();
@@ -47,13 +47,13 @@ class ConfigFileWatcherImpl
   void FinishStopping();
 
   // Called every time the host configuration file is updated.
-  void OnConfigUpdated(const FilePath& path, bool error);
+  void OnConfigUpdated(const base::FilePath& path, bool error);
 
   // Reads the configuration file and passes it to the delegate.
   void ReloadConfig();
 
   std::string config_;
-  FilePath config_path_;
+  base::FilePath config_path_;
 
   scoped_ptr<base::DelayTimer<ConfigFileWatcherImpl> > config_updated_timer_;
 
@@ -85,7 +85,7 @@ ConfigFileWatcher::~ConfigFileWatcher() {
   impl_ = NULL;
 }
 
-void ConfigFileWatcher::Watch(const FilePath& config_path) {
+void ConfigFileWatcher::Watch(const base::FilePath& config_path) {
   impl_->Watch(config_path);
 }
 
@@ -100,7 +100,7 @@ ConfigFileWatcherImpl::ConfigFileWatcherImpl(
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 }
 
-void ConfigFileWatcherImpl::Watch(const FilePath& config_path) {
+void ConfigFileWatcherImpl::Watch(const base::FilePath& config_path) {
   if (!io_task_runner_->BelongsToCurrentThread()) {
     io_task_runner_->PostTask(
         FROM_HERE,
@@ -156,7 +156,8 @@ void ConfigFileWatcherImpl::FinishStopping() {
   config_watcher_.reset(NULL);
 }
 
-void ConfigFileWatcherImpl::OnConfigUpdated(const FilePath& path, bool error) {
+void ConfigFileWatcherImpl::OnConfigUpdated(const base::FilePath& path,
+                                            bool error) {
   DCHECK(io_task_runner_->BelongsToCurrentThread());
 
   // Call ReloadConfig() after a short delay, so that we will not try to read
diff --git a/remoting/host/config_file_watcher.h b/remoting/host/config_file_watcher.h
index 83e971a4f1095a..97622969c4ecad 100644
--- a/remoting/host/config_file_watcher.h
+++ b/remoting/host/config_file_watcher.h
@@ -17,7 +17,7 @@ class SingleThreadTaskRunner;
 namespace remoting {
 
 extern const char kHostConfigSwitchName[];
-extern const FilePath::CharType kDefaultHostConfigFile[];
+extern const base::FilePath::CharType kDefaultHostConfigFile[];
 
 class ConfigFileWatcherImpl;
 
@@ -44,7 +44,7 @@ class ConfigFileWatcher {
   virtual ~ConfigFileWatcher();
 
   // Starts watching |config_path|.
-  void Watch(const FilePath& config_path);
+  void Watch(const base::FilePath& config_path);
 
  private:
   scoped_refptr<ConfigFileWatcherImpl> impl_;
diff --git a/remoting/host/daemon_process.cc b/remoting/host/daemon_process.cc
index e97341b0ab9a5d..84f5b916a74907 100644
--- a/remoting/host/daemon_process.cc
+++ b/remoting/host/daemon_process.cc
@@ -151,8 +151,8 @@ void DaemonProcess::Initialize() {
   DCHECK(caller_task_runner()->BelongsToCurrentThread());
 
   // Get the name of the host configuration file.
-  FilePath default_config_dir = remoting::GetConfigDir();
-  FilePath config_path = default_config_dir.Append(kDefaultHostConfigFile);
+  base::FilePath default_config_dir = remoting::GetConfigDir();
+  base::FilePath config_path = default_config_dir.Append(kDefaultHostConfigFile);
   const CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(kHostConfigSwitchName)) {
     config_path = command_line->GetSwitchValuePath(kHostConfigSwitchName);
diff --git a/remoting/host/daemon_process.h b/remoting/host/daemon_process.h
index 801e271c779996..45952bb247c921 100644
--- a/remoting/host/daemon_process.h
+++ b/remoting/host/daemon_process.h
@@ -20,8 +20,6 @@
 #include "remoting/host/config_file_watcher.h"
 #include "remoting/host/worker_process_ipc_delegate.h"
 
-class FilePath;
-
 namespace remoting {
 
 class AutoThreadTaskRunner;
diff --git a/remoting/host/daemon_process_win.cc b/remoting/host/daemon_process_win.cc
index 378eb520a812bf..51ee12a6ec4524 100644
--- a/remoting/host/daemon_process_win.cc
+++ b/remoting/host/daemon_process_win.cc
@@ -143,7 +143,7 @@ void DaemonProcessWin::LaunchNetworkProcess() {
   DCHECK(!network_launcher_);
 
   // Construct the host binary name.
-  FilePath host_binary;
+  base::FilePath host_binary;
   if (!GetInstalledBinaryPath(kHostBinaryName, &host_binary)) {
     Stop();
     return;
diff --git a/remoting/host/desktop_process_main.cc b/remoting/host/desktop_process_main.cc
index fa678de69ef438..5801c8d7647a5b 100644
--- a/remoting/host/desktop_process_main.cc
+++ b/remoting/host/desktop_process_main.cc
@@ -47,7 +47,7 @@ const char kUsageMessage[] =
   "Options:\n"
   "  --help, --?     - Print this message.\n";
 
-void Usage(const FilePath& program_name) {
+void Usage(const base::FilePath& program_name) {
   std::string display_name = UTF16ToUTF8(program_name.LossyDisplayName());
   LOG(INFO) << StringPrintf(kUsageMessage, display_name.c_str());
 }
@@ -125,7 +125,7 @@ int CALLBACK WinMain(HINSTANCE instance,
   // Mark the process as DPI-aware, so Windows won't scale coordinates in APIs.
   // N.B. This API exists on Vista and above.
   if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
-    FilePath path(base::GetNativeLibraryName(UTF8ToUTF16("user32")));
+    base::FilePath path(base::GetNativeLibraryName(UTF8ToUTF16("user32")));
     base::ScopedNativeLibrary user32(path);
     CHECK(user32.is_valid());
 
diff --git a/remoting/host/desktop_session_win.cc b/remoting/host/desktop_session_win.cc
index ac287643eabe70..288aba5c496e2e 100644
--- a/remoting/host/desktop_session_win.cc
+++ b/remoting/host/desktop_session_win.cc
@@ -18,7 +18,7 @@ using base::win::ScopedHandle;
 
 namespace {
 
-const FilePath::CharType kDesktopBinaryName[] =
+const base::FilePath::CharType kDesktopBinaryName[] =
     FILE_PATH_LITERAL("remoting_desktop.exe");
 
 // The security descriptor of the daemon IPC endpoint. It gives full access
@@ -95,7 +95,7 @@ void DesktopSessionWin::OnSessionAttached(uint32 session_id) {
 
   // Construct the host binary name.
   if (desktop_binary_.empty()) {
-    FilePath dir_path;
+    base::FilePath dir_path;
     if (!PathService::Get(base::DIR_EXE, &dir_path)) {
       LOG(ERROR) << "Failed to get the executable file name.";
       OnPermanentError();
diff --git a/remoting/host/desktop_session_win.h b/remoting/host/desktop_session_win.h
index 89343c9f286e84..53b2fefa8a9b22 100644
--- a/remoting/host/desktop_session_win.h
+++ b/remoting/host/desktop_session_win.h
@@ -74,7 +74,7 @@ class DesktopSessionWin
   scoped_refptr<AutoThreadTaskRunner> io_task_runner_;
 
   // Contains the full path to the desktop binary.
-  FilePath desktop_binary_;
+  base::FilePath desktop_binary_;
 
   // Handle of the desktop process.
   base::win::ScopedHandle desktop_process_;
diff --git a/remoting/host/host_key_pair_unittest.cc b/remoting/host/host_key_pair_unittest.cc
index f19674f2ca5c82..2aa921c3115dc4 100644
--- a/remoting/host/host_key_pair_unittest.cc
+++ b/remoting/host/host_key_pair_unittest.cc
@@ -33,7 +33,7 @@ class HostKeyPairTest : public testing::Test {
  protected:
   virtual void SetUp() {
     ASSERT_TRUE(test_dir_.CreateUniqueTempDir());
-    FilePath config_path = test_dir_.path().AppendASCII("test_config.json");
+    base::FilePath config_path = test_dir_.path().AppendASCII("test_config.json");
     config_.reset(new JsonHostConfig(config_path));
   }
 
diff --git a/remoting/host/ipc_constants.cc b/remoting/host/ipc_constants.cc
index 36d4beade4c2d3..9aac903d914964 100644
--- a/remoting/host/ipc_constants.cc
+++ b/remoting/host/ipc_constants.cc
@@ -12,20 +12,21 @@ namespace remoting {
 
 const char kDaemonPipeSwitchName[] = "daemon-pipe";
 
-const FilePath::CharType kDaemonBinaryName[] =
+const base::FilePath::CharType kDaemonBinaryName[] =
     FILE_PATH_LITERAL("remoting_daemon");
 
-const FilePath::CharType kHostBinaryName[] = FILE_PATH_LITERAL("remoting_host");
+const base::FilePath::CharType kHostBinaryName[] =
+    FILE_PATH_LITERAL("remoting_host");
 
-bool GetInstalledBinaryPath(const FilePath::StringType& binary,
-                            FilePath* full_path) {
-  FilePath dir_path;
+bool GetInstalledBinaryPath(const base::FilePath::StringType& binary,
+                            base::FilePath* full_path) {
+  base::FilePath dir_path;
   if (!PathService::Get(base::DIR_EXE, &dir_path)) {
     LOG(ERROR) << "Failed to get the executable file name.";
     return false;
   }
 
-  FilePath path = dir_path.Append(binary);
+  base::FilePath path = dir_path.Append(binary);
 
 #if defined(OS_WIN)
   path = path.ReplaceExtension(FILE_PATH_LITERAL("exe"));
diff --git a/remoting/host/ipc_constants.h b/remoting/host/ipc_constants.h
index 0e6ddc6fb3f388..d99020667b0096 100644
--- a/remoting/host/ipc_constants.h
+++ b/remoting/host/ipc_constants.h
@@ -13,14 +13,14 @@ namespace remoting {
 extern const char kDaemonPipeSwitchName[];
 
 // Name of the daemon process binary.
-extern const FilePath::CharType kDaemonBinaryName[];
+extern const base::FilePath::CharType kDaemonBinaryName[];
 
 // Name of the host process binary.
-extern const FilePath::CharType kHostBinaryName[];
+extern const base::FilePath::CharType kHostBinaryName[];
 
 // Returns the full path to an installed |binary| in |full_path|.
-bool GetInstalledBinaryPath(const FilePath::StringType& binary,
-                            FilePath* full_path);
+bool GetInstalledBinaryPath(const base::FilePath::StringType& binary,
+                            base::FilePath* full_path);
 
 }  // namespace remoting
 
diff --git a/remoting/host/json_host_config.cc b/remoting/host/json_host_config.cc
index 82a9cf7d79564b..d25f4b5ae8907d 100644
--- a/remoting/host/json_host_config.cc
+++ b/remoting/host/json_host_config.cc
@@ -15,7 +15,7 @@
 
 namespace remoting {
 
-JsonHostConfig::JsonHostConfig(const FilePath& filename)
+JsonHostConfig::JsonHostConfig(const base::FilePath& filename)
     : filename_(filename) {
 }
 
diff --git a/remoting/host/json_host_config.h b/remoting/host/json_host_config.h
index c0148cca32af3c..c8a4abab896623 100644
--- a/remoting/host/json_host_config.h
+++ b/remoting/host/json_host_config.h
@@ -19,7 +19,7 @@ namespace remoting {
 // JsonHostConfig implements MutableHostConfig for JSON file.
 class JsonHostConfig : public InMemoryHostConfig {
  public:
-  JsonHostConfig(const FilePath& filename);
+  JsonHostConfig(const base::FilePath& filename);
   virtual ~JsonHostConfig();
 
   virtual bool Read();
@@ -34,7 +34,7 @@ class JsonHostConfig : public InMemoryHostConfig {
   bool SetSerializedData(const std::string& config);
 
  private:
-  FilePath filename_;
+  base::FilePath filename_;
 
   DISALLOW_COPY_AND_ASSIGN(JsonHostConfig);
 };
diff --git a/remoting/host/json_host_config_unittest.cc b/remoting/host/json_host_config_unittest.cc
index 4aedf3df216a10..76f2912f49bcbe 100644
--- a/remoting/host/json_host_config_unittest.cc
+++ b/remoting/host/json_host_config_unittest.cc
@@ -24,7 +24,7 @@ const char* kTestConfig =
 
 class JsonHostConfigTest : public testing::Test {
  protected:
-  static void WriteTestFile(const FilePath& filename) {
+  static void WriteTestFile(const base::FilePath& filename) {
     file_util::WriteFile(filename, kTestConfig, std::strlen(kTestConfig));
   }
 
@@ -34,7 +34,7 @@ class JsonHostConfigTest : public testing::Test {
 
 TEST_F(JsonHostConfigTest, InvalidFile) {
   ASSERT_TRUE(test_dir_.CreateUniqueTempDir());
-  FilePath non_existent_file =
+  base::FilePath non_existent_file =
       test_dir_.path().AppendASCII("non_existent.json");
   JsonHostConfig target(non_existent_file);
   EXPECT_FALSE(target.Read());
@@ -42,7 +42,7 @@ TEST_F(JsonHostConfigTest, InvalidFile) {
 
 TEST_F(JsonHostConfigTest, Read) {
   ASSERT_TRUE(test_dir_.CreateUniqueTempDir());
-  FilePath test_file = test_dir_.path().AppendASCII("read.json");
+  base::FilePath test_file = test_dir_.path().AppendASCII("read.json");
   WriteTestFile(test_file);
   JsonHostConfig target(test_file);
   ASSERT_TRUE(target.Read());
@@ -65,7 +65,7 @@ TEST_F(JsonHostConfigTest, Read) {
 TEST_F(JsonHostConfigTest, Write) {
   ASSERT_TRUE(test_dir_.CreateUniqueTempDir());
 
-  FilePath test_file = test_dir_.path().AppendASCII("write.json");
+  base::FilePath test_file = test_dir_.path().AppendASCII("write.json");
   WriteTestFile(test_file);
   JsonHostConfig target(test_file);
   ASSERT_TRUE(target.Read());
diff --git a/remoting/host/linux/audio_pipe_reader.cc b/remoting/host/linux/audio_pipe_reader.cc
index d396e89ad9995c..c66839b7d0c59c 100644
--- a/remoting/host/linux/audio_pipe_reader.cc
+++ b/remoting/host/linux/audio_pipe_reader.cc
@@ -47,7 +47,7 @@ const int kPipeBufferSizeBytes = kPipeBufferSizeMs * kSampleBytesPerSecond /
 // static
 scoped_refptr<AudioPipeReader> AudioPipeReader::Create(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    const FilePath& pipe_name) {
+    const base::FilePath& pipe_name) {
   // Create a reference to the new AudioPipeReader before posting the
   // StartOnAudioThread task, otherwise it may be deleted on the audio
   // thread before we return.
@@ -58,7 +58,7 @@ scoped_refptr<AudioPipeReader> AudioPipeReader::Create(
   return pipe_reader;
 }
 
-void AudioPipeReader::StartOnAudioThread(const FilePath& pipe_name) {
+void AudioPipeReader::StartOnAudioThread(const base::FilePath& pipe_name) {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   pipe_fd_ = HANDLE_EINTR(open(
diff --git a/remoting/host/linux/audio_pipe_reader.h b/remoting/host/linux/audio_pipe_reader.h
index b0c56e75291628..a373ac3a4e0f45 100644
--- a/remoting/host/linux/audio_pipe_reader.h
+++ b/remoting/host/linux/audio_pipe_reader.h
@@ -12,7 +12,9 @@
 #include "base/time.h"
 #include "base/timer.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace remoting {
 
@@ -33,7 +35,7 @@ class AudioPipeReader
   // |task_runner| specifies the IO thread to use to read data from the pipe.
   static scoped_refptr<AudioPipeReader> Create(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-      const FilePath& pipe_name);
+      const base::FilePath& pipe_name);
 
   // Register or unregister an observer. Each observer receives data on the
   // thread on which it was registered and guaranteed not to be called after
@@ -53,7 +55,7 @@ class AudioPipeReader
   AudioPipeReader(scoped_refptr<base::SingleThreadTaskRunner> task_runner);
   virtual ~AudioPipeReader();
 
-  void StartOnAudioThread(const FilePath& pipe_name);
+  void StartOnAudioThread(const base::FilePath& pipe_name);
   void StartTimer();
   void DoCapture();
   void WaitForPipeReadable();
diff --git a/remoting/host/policy_hack/policy_watcher_linux.cc b/remoting/host/policy_hack/policy_watcher_linux.cc
index 0df6120f1887ac..1dc7b218d39edb 100644
--- a/remoting/host/policy_hack/policy_watcher_linux.cc
+++ b/remoting/host/policy_hack/policy_watcher_linux.cc
@@ -32,7 +32,7 @@ namespace policy_hack {
 
 namespace {
 
-const FilePath::CharType kPolicyDir[] =
+const base::FilePath::CharType kPolicyDir[] =
   // Always read the Chrome policies (even on Chromium) so that policy
   // enforcement can't be bypassed by running Chromium.
   FILE_PATH_LITERAL("/etc/opt/chrome/policies/managed");
@@ -47,7 +47,7 @@ const int kSettleIntervalSeconds = 5;
 class PolicyWatcherLinux : public PolicyWatcher {
  public:
   PolicyWatcherLinux(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-                     const FilePath& config_dir)
+                     const base::FilePath& config_dir)
       : PolicyWatcher(task_runner),
         config_dir_(config_dir),
         ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
@@ -89,7 +89,7 @@ class PolicyWatcherLinux : public PolicyWatcher {
   }
 
  private:
-  void OnFilePathChanged(const FilePath& path, bool error) {
+  void OnFilePathChanged(const base::FilePath& path, bool error) {
     DCHECK(OnPolicyWatcherThread());
 
     if (!error)
@@ -113,7 +113,7 @@ class PolicyWatcherLinux : public PolicyWatcher {
     file_util::FileEnumerator file_enumerator(config_dir_,
                                               false,
                                               file_util::FileEnumerator::FILES);
-    for (FilePath config_file = file_enumerator.Next();
+    for (base::FilePath config_file = file_enumerator.Next();
          !config_file.empty();
          config_file = file_enumerator.Next()) {
       if (file_util::GetFileInfo(config_file, &file_info) &&
@@ -130,16 +130,16 @@ class PolicyWatcherLinux : public PolicyWatcher {
   scoped_ptr<DictionaryValue> Load() {
     DCHECK(OnPolicyWatcherThread());
     // Enumerate the files and sort them lexicographically.
-    std::set<FilePath> files;
+    std::set<base::FilePath> files;
     file_util::FileEnumerator file_enumerator(config_dir_, false,
                                               file_util::FileEnumerator::FILES);
-    for (FilePath config_file_path = file_enumerator.Next();
+    for (base::FilePath config_file_path = file_enumerator.Next();
          !config_file_path.empty(); config_file_path = file_enumerator.Next())
       files.insert(config_file_path);
 
     // Start with an empty dictionary and merge the files' contents.
     scoped_ptr<DictionaryValue> policy(new DictionaryValue());
-    for (std::set<FilePath>::iterator config_file_iter = files.begin();
+    for (std::set<base::FilePath>::iterator config_file_iter = files.begin();
          config_file_iter != files.end(); ++config_file_iter) {
       JSONFileValueSerializer deserializer(*config_file_iter);
       deserializer.set_allow_trailing_comma(true);
@@ -239,7 +239,7 @@ class PolicyWatcherLinux : public PolicyWatcher {
   // non-local filesystem involved.
   base::Time last_modification_clock_;
 
-  const FilePath config_dir_;
+  const base::FilePath config_dir_;
 
   // Allows us to cancel any inflight FileWatcher events or scheduled reloads.
   base::WeakPtrFactory<PolicyWatcherLinux> weak_factory_;
@@ -247,7 +247,7 @@ class PolicyWatcherLinux : public PolicyWatcher {
 
 PolicyWatcher* PolicyWatcher::Create(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
-  FilePath policy_dir(kPolicyDir);
+  base::FilePath policy_dir(kPolicyDir);
   return new PolicyWatcherLinux(task_runner, policy_dir);
 }
 
diff --git a/remoting/host/remoting_me2me_host.cc b/remoting/host/remoting_me2me_host.cc
index 0e3d94871a0124..995b52d4a63150 100644
--- a/remoting/host/remoting_me2me_host.cc
+++ b/remoting/host/remoting_me2me_host.cc
@@ -273,7 +273,7 @@ class HostProcess
   scoped_ptr<IPC::ChannelProxy> daemon_channel_;
 
   // Created on the UI thread but used from the network thread.
-  FilePath host_config_path_;
+  base::FilePath host_config_path_;
   scoped_ptr<DesktopEnvironmentFactory> desktop_environment_factory_;
 
   // Accessed on the network thread.
@@ -402,7 +402,7 @@ bool HostProcess::InitWithCommandLine(const CommandLine* cmd_line) {
         context_->network_task_runner()));
   }
 
-  FilePath default_config_dir = remoting::GetConfigDir();
+  base::FilePath default_config_dir = remoting::GetConfigDir();
   host_config_path_ = default_config_dir.Append(kDefaultHostConfigFile);
   if (cmd_line->HasSwitch(kHostConfigSwitchName)) {
     host_config_path_ = cmd_line->GetSwitchValuePath(kHostConfigSwitchName);
@@ -427,7 +427,7 @@ void HostProcess::OnConfigUpdated(
   LOG(INFO) << "Processing new host configuration.";
 
   serialized_config_ = serialized_config;
-  scoped_ptr<JsonHostConfig> config(new JsonHostConfig(FilePath()));
+  scoped_ptr<JsonHostConfig> config(new JsonHostConfig(base::FilePath()));
   if (!config->SetSerializedData(serialized_config)) {
     LOG(ERROR) << "Invalid configuration.";
     ShutdownHost(kInvalidHostConfigurationExitCode);
@@ -558,7 +558,7 @@ void HostProcess::StartOnUiThread() {
 #if defined(OS_LINUX)
   // If an audio pipe is specific on the command-line then initialize
   // AudioCapturerLinux to capture from it.
-  FilePath audio_pipe_name = CommandLine::ForCurrentProcess()->
+  base::FilePath audio_pipe_name = CommandLine::ForCurrentProcess()->
       GetSwitchValuePath(kAudioPipeSwitchName);
   if (!audio_pipe_name.empty()) {
     remoting::AudioCapturerLinux::InitializePipeReader(
@@ -641,7 +641,7 @@ void HostProcess::ShutdownOnUiThread() {
   // thread will remain in-use and prevent the process from exiting.
   // TODO(wez): DesktopEnvironmentFactory should own the pipe reader.
   // See crbug.com/161373 and crbug.com/104544.
-  AudioCapturerLinux::InitializePipeReader(NULL, FilePath());
+  AudioCapturerLinux::InitializePipeReader(NULL, base::FilePath());
 #endif
 }
 
@@ -1135,7 +1135,7 @@ int CALLBACK WinMain(HINSTANCE instance,
   // Mark the process as DPI-aware, so Windows won't scale coordinates in APIs.
   // N.B. This API exists on Vista and above.
   if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
-    FilePath path(base::GetNativeLibraryName(UTF8ToUTF16("user32")));
+    base::FilePath path(base::GetNativeLibraryName(UTF8ToUTF16("user32")));
     base::ScopedNativeLibrary user32(path);
     CHECK(user32.is_valid());
 
diff --git a/remoting/host/sas_injector_win.cc b/remoting/host/sas_injector_win.cc
index efab8e645bdcf9..a9bb80b6b3330e 100644
--- a/remoting/host/sas_injector_win.cc
+++ b/remoting/host/sas_injector_win.cc
@@ -22,7 +22,7 @@ namespace remoting {
 namespace {
 
 // Names of the API and library implementing software SAS generation.
-const FilePath::CharType kSasDllFileName[] = FILE_PATH_LITERAL("sas.dll");
+const base::FilePath::CharType kSasDllFileName[] = FILE_PATH_LITERAL("sas.dll");
 const char kSendSasName[] = "SendSAS";
 
 // The prototype of SendSAS().
@@ -144,7 +144,7 @@ bool SasInjectorWin::InjectSas() {
   // Load sas.dll. The library is expected to be in the same folder as this
   // binary.
   if (!sas_dll_.is_valid()) {
-    FilePath dir_path;
+    base::FilePath dir_path;
     if (!PathService::Get(base::DIR_EXE, &dir_path)) {
       LOG(ERROR) << "Failed to get the executable file name.";
       return false;
diff --git a/remoting/host/setup/daemon_controller_linux.cc b/remoting/host/setup/daemon_controller_linux.cc
index 121d77a658f048..598b1dbf17d047 100644
--- a/remoting/host/setup/daemon_controller_linux.cc
+++ b/remoting/host/setup/daemon_controller_linux.cc
@@ -68,7 +68,7 @@ class DaemonControllerLinux : public remoting::DaemonController {
       const GetUsageStatsConsentCallback& done) OVERRIDE;
 
  private:
-  FilePath GetConfigPath();
+  base::FilePath GetConfigPath();
 
   void DoGetConfig(const GetConfigCallback& callback);
   void DoSetConfigAndStart(scoped_ptr<base::DictionaryValue> config,
@@ -88,8 +88,8 @@ DaemonControllerLinux::DaemonControllerLinux()
   file_io_thread_.Start();
 }
 
-static bool GetScriptPath(FilePath* result) {
-  FilePath candidate_exe(kDaemonScript);
+static bool GetScriptPath(base::FilePath* result) {
+  base::FilePath candidate_exe(kDaemonScript);
   if (access(candidate_exe.value().c_str(), X_OK) == 0) {
     *result = candidate_exe;
     return true;
@@ -106,7 +106,7 @@ static bool RunHostScriptWithTimeout(
   if (getuid() == 0) {
     return false;
   }
-  FilePath script_path;
+  base::FilePath script_path;
   if (!GetScriptPath(&script_path)) {
     return false;
   }
@@ -200,7 +200,7 @@ void DaemonControllerLinux::GetVersion(
       done_callback));
 }
 
-FilePath DaemonControllerLinux::GetConfigPath() {
+base::FilePath DaemonControllerLinux::GetConfigPath() {
   std::string filename = "host#" + GetMd5(net::GetHostName()) + ".json";
   return file_util::GetHomeDir().
       Append(".config/chrome-remote-desktop").Append(filename);
@@ -245,7 +245,7 @@ void DaemonControllerLinux::DoSetConfigAndStart(
   }
 
   // Ensure the configuration directory exists.
-  FilePath config_dir = GetConfigPath().DirName();
+  base::FilePath config_dir = GetConfigPath().DirName();
   if (!file_util::DirectoryExists(config_dir) &&
       !file_util::CreateDirectory(config_dir)) {
     LOG(ERROR) << "Failed to create config directory " << config_dir.value();
@@ -314,7 +314,7 @@ void DaemonControllerLinux::DoStop(const CompletionCallback& done_callback) {
 
 void DaemonControllerLinux::DoGetVersion(
     const GetVersionCallback& done_callback) {
-  FilePath script_path;
+  base::FilePath script_path;
   if (!GetScriptPath(&script_path)) {
     done_callback.Run("");
     return;
diff --git a/remoting/host/setup/daemon_controller_mac.cc b/remoting/host/setup/daemon_controller_mac.cc
index 430077cdf890bd..95e1b1fd3e9f0c 100644
--- a/remoting/host/setup/daemon_controller_mac.cc
+++ b/remoting/host/setup/daemon_controller_mac.cc
@@ -174,7 +174,7 @@ void DaemonControllerMac::GetUsageStatsConsent(
 }
 
 void DaemonControllerMac::DoGetConfig(const GetConfigCallback& callback) {
-  FilePath config_path(kHostConfigFilePath);
+  base::FilePath config_path(kHostConfigFilePath);
   JsonHostConfig host_config(config_path);
   scoped_ptr<base::DictionaryValue> config;
 
@@ -227,7 +227,7 @@ void DaemonControllerMac::DoSetConfigAndStart(
 void DaemonControllerMac::DoUpdateConfig(
     scoped_ptr<base::DictionaryValue> config,
     const CompletionCallback& done_callback) {
-  FilePath config_file_path(kHostConfigFilePath);
+  base::FilePath config_file_path(kHostConfigFilePath);
   JsonHostConfig config_file(config_file_path);
   if (!config_file.Read()) {
     done_callback.Run(RESULT_FAILED);
@@ -246,7 +246,7 @@ void DaemonControllerMac::DoUpdateConfig(
 void DaemonControllerMac::DoGetUsageStatsConsent(
     const GetUsageStatsConsentCallback& callback) {
   bool allowed = false;
-  FilePath config_file_path(kHostConfigFilePath);
+  base::FilePath config_file_path(kHostConfigFilePath);
   JsonHostConfig host_config(config_file_path);
   if (host_config.Read()) {
     host_config.GetBoolean(kUsageStatsConsentConfigPath, &allowed);
@@ -266,7 +266,7 @@ void DaemonControllerMac::ShowPreferencePane(
 
 bool DaemonControllerMac::DoShowPreferencePane(const std::string& config_data) {
   if (!config_data.empty()) {
-    FilePath config_path;
+    base::FilePath config_path;
     if (!file_util::GetTempDir(&config_path)) {
       LOG(ERROR) << "Failed to get filename for saving configuration data.";
       return false;
@@ -282,7 +282,7 @@ bool DaemonControllerMac::DoShowPreferencePane(const std::string& config_data) {
     }
   }
 
-  FilePath pane_path;
+  base::FilePath pane_path;
   // TODO(lambroslambrou): Use NSPreferencePanesDirectory once we start
   // building against SDK 10.6.
   if (!base::mac::GetLocalDirectory(NSLibraryDirectory, &pane_path)) {
diff --git a/remoting/host/usage_stats_consent_mac.cc b/remoting/host/usage_stats_consent_mac.cc
index 00655a4b9f4c93..db82d92c972d03 100644
--- a/remoting/host/usage_stats_consent_mac.cc
+++ b/remoting/host/usage_stats_consent_mac.cc
@@ -23,7 +23,7 @@ bool GetUsageStatsConsent(bool* allowed, bool* set_by_policy) {
   // which itself should happen as early as possible during startup.
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(kHostConfigSwitchName)) {
-    FilePath config_file_path =
+    base::FilePath config_file_path =
         command_line->GetSwitchValuePath(kHostConfigSwitchName);
     JsonHostConfig host_config(config_file_path);
     if (host_config.Read()) {
diff --git a/remoting/host/win/elevated_controller.cc b/remoting/host/win/elevated_controller.cc
index a43203d1c1f7fc..024ca3444ea04e 100644
--- a/remoting/host/win/elevated_controller.cc
+++ b/remoting/host/win/elevated_controller.cc
@@ -32,14 +32,14 @@ namespace {
 const size_t kMaxConfigFileSize = 1024 * 1024;
 
 // The host configuration file name.
-const FilePath::CharType kConfigFileName[] = FILE_PATH_LITERAL("host.json");
+const base::FilePath::CharType kConfigFileName[] = FILE_PATH_LITERAL("host.json");
 
 // The unprivileged configuration file name.
-const FilePath::CharType kUnprivilegedConfigFileName[] =
+const base::FilePath::CharType kUnprivilegedConfigFileName[] =
     FILE_PATH_LITERAL("host_unprivileged.json");
 
 // The extension for the temporary file.
-const FilePath::CharType kTempFileExtension[] = FILE_PATH_LITERAL("json~");
+const base::FilePath::CharType kTempFileExtension[] = FILE_PATH_LITERAL("json~");
 
 // The host configuration file security descriptor that enables full access to
 // Local System and built-in administrators only.
@@ -92,7 +92,7 @@ bool IsClientAdmin() {
 
 // Reads and parses the configuration file up to |kMaxConfigFileSize| in
 // size.
-HRESULT ReadConfig(const FilePath& filename,
+HRESULT ReadConfig(const base::FilePath& filename,
                    scoped_ptr<base::DictionaryValue>* config_out) {
 
   // Read raw data from the configuration file.
@@ -137,12 +137,12 @@ HRESULT ReadConfig(const FilePath& filename,
   return S_OK;
 }
 
-FilePath GetTempLocationFor(const FilePath& filename) {
+base::FilePath GetTempLocationFor(const base::FilePath& filename) {
   return filename.ReplaceExtension(kTempFileExtension);
 }
 
 // Writes a config file to a temporary location.
-HRESULT WriteConfigFileToTemp(const FilePath& filename,
+HRESULT WriteConfigFileToTemp(const base::FilePath& filename,
                               const char* security_descriptor,
                               const char* content,
                               size_t length) {
@@ -161,7 +161,7 @@ HRESULT WriteConfigFileToTemp(const FilePath& filename,
   security_attributes.bInheritHandle = FALSE;
 
   // Create a temporary file and write configuration to it.
-  FilePath tempname = GetTempLocationFor(filename);
+  base::FilePath tempname = GetTempLocationFor(filename);
   base::win::ScopedHandle file(
       CreateFileW(tempname.value().c_str(),
                   GENERIC_WRITE,
@@ -190,10 +190,10 @@ HRESULT WriteConfigFileToTemp(const FilePath& filename,
 }
 
 // Moves a config file from its temporary location to its permanent location.
-HRESULT MoveConfigFileFromTemp(const FilePath& filename) {
+HRESULT MoveConfigFileFromTemp(const base::FilePath& filename) {
   // Now that the configuration is stored successfully replace the actual
   // configuration file.
-  FilePath tempname = GetTempLocationFor(filename);
+  base::FilePath tempname = GetTempLocationFor(filename);
   if (!MoveFileExW(tempname.value().c_str(),
                    filename.value().c_str(),
                    MOVEFILE_REPLACE_EXISTING)) {
@@ -253,7 +253,7 @@ HRESULT WriteConfig(const char* content, size_t length, HWND owner_window) {
   base::JSONWriter::Write(&unprivileged_config_dict, &unprivileged_config_str);
 
   // Write the full configuration file to a temporary location.
-  FilePath full_config_file_path =
+  base::FilePath full_config_file_path =
       remoting::GetConfigDir().Append(kConfigFileName);
   HRESULT hr = WriteConfigFileToTemp(full_config_file_path,
                                      kConfigFileSecurityDescriptor,
@@ -264,7 +264,7 @@ HRESULT WriteConfig(const char* content, size_t length, HWND owner_window) {
   }
 
   // Write the unprivileged configuration file to a temporary location.
-  FilePath unprivileged_config_file_path =
+  base::FilePath unprivileged_config_file_path =
       remoting::GetConfigDir().Append(kUnprivilegedConfigFileName);
   hr = WriteConfigFileToTemp(unprivileged_config_file_path,
                              kUnprivilegedConfigFileSecurityDescriptor,
@@ -302,7 +302,7 @@ void ElevatedController::FinalRelease() {
 }
 
 STDMETHODIMP ElevatedController::GetConfig(BSTR* config_out) {
-  FilePath config_dir = remoting::GetConfigDir();
+  base::FilePath config_dir = remoting::GetConfigDir();
 
   // Read the unprivileged part of host configuration.
   scoped_ptr<base::DictionaryValue> config;
@@ -347,7 +347,7 @@ STDMETHODIMP ElevatedController::GetVersion(BSTR* version_out) {
 
 STDMETHODIMP ElevatedController::SetConfig(BSTR config) {
   // Determine the config directory path and create it if necessary.
-  FilePath config_dir = remoting::GetConfigDir();
+  base::FilePath config_dir = remoting::GetConfigDir();
   if (!file_util::CreateDirectory(config_dir)) {
     return HRESULT_FROM_WIN32(ERROR_ACCESS_DENIED);
   }
@@ -462,7 +462,7 @@ STDMETHODIMP ElevatedController::UpdateConfig(BSTR config) {
     }
   }
   // Get the old config.
-  FilePath config_dir = remoting::GetConfigDir();
+  base::FilePath config_dir = remoting::GetConfigDir();
   scoped_ptr<base::DictionaryValue> config_old;
   HRESULT hr = ReadConfig(config_dir.Append(kConfigFileName), &config_old);
   if (FAILED(hr)) {
diff --git a/remoting/host/win/host_service.cc b/remoting/host/win/host_service.cc
index 84c7f7cfa45b8a..51f44649cd7e46 100644
--- a/remoting/host/win/host_service.cc
+++ b/remoting/host/win/host_service.cc
@@ -84,7 +84,7 @@ const wchar_t kUsageMessage[] =
 const char* kCopiedSwitchNames[] = {
     "host-config", "daemon-pipe", switches::kV, switches::kVModule };
 
-void usage(const FilePath& program_name) {
+void usage(const base::FilePath& program_name) {
   LOG(INFO) << StringPrintf(kUsageMessage,
                             UTF16ToWide(program_name.value()).c_str());
 }
@@ -231,7 +231,7 @@ void HostService::CreateLauncher(
 
 int HostService::Elevate() {
   // Get the name of the binary to launch.
-  FilePath binary =
+  base::FilePath binary =
       CommandLine::ForCurrentProcess()->GetSwitchValuePath(kElevateSwitchName);
 
   // Create the child process command line by copying known switches from our
diff --git a/remoting/host/win/launch_process_with_token.cc b/remoting/host/win/launch_process_with_token.cc
index 51b390034fe7be..fffa9830f7ec6c 100644
--- a/remoting/host/win/launch_process_with_token.cc
+++ b/remoting/host/win/launch_process_with_token.cc
@@ -64,7 +64,7 @@ bool ConnectToExecutionServer(uint32 session_id,
 
   // Use winsta!WinStationQueryInformationW() to determine the process creation
   // pipe name for the session.
-  FilePath winsta_path(base::GetNativeLibraryName(UTF8ToUTF16("winsta")));
+  base::FilePath winsta_path(base::GetNativeLibraryName(UTF8ToUTF16("winsta")));
   base::ScopedNativeLibrary winsta(winsta_path);
   if (winsta.is_valid()) {
     PWINSTATIONQUERYINFORMATIONW win_station_query_information =
@@ -293,7 +293,7 @@ bool ReceiveCreateProcessResponse(
 // Sends a remote process create request to the execution server.
 bool SendCreateProcessRequest(
     HANDLE pipe,
-    const FilePath::StringType& application_name,
+    const base::FilePath::StringType& application_name,
     const CommandLine::StringType& command_line,
     DWORD creation_flags,
     const char16* desktop_name) {
@@ -376,7 +376,7 @@ bool SendCreateProcessRequest(
 // OS functionality and will likely not work on anything but XP or W2K3.
 bool CreateRemoteSessionProcess(
     uint32 session_id,
-    const FilePath::StringType& application_name,
+    const base::FilePath::StringType& application_name,
     const CommandLine::StringType& command_line,
     DWORD creation_flags,
     const char16* desktop_name,
@@ -552,7 +552,7 @@ bool CreateSessionToken(uint32 session_id, ScopedHandle* token_out) {
   return true;
 }
 
-bool LaunchProcessWithToken(const FilePath& binary,
+bool LaunchProcessWithToken(const base::FilePath& binary,
                             const CommandLine::StringType& command_line,
                             HANDLE user_token,
                             SECURITY_ATTRIBUTES* process_attributes,
@@ -562,7 +562,7 @@ bool LaunchProcessWithToken(const FilePath& binary,
                             const char16* desktop_name,
                             ScopedHandle* process_out,
                             ScopedHandle* thread_out) {
-  FilePath::StringType application_name = binary.value();
+  base::FilePath::StringType application_name = binary.value();
 
   STARTUPINFOW startup_info;
   memset(&startup_info, 0, sizeof(startup_info));
diff --git a/remoting/host/win/launch_process_with_token.h b/remoting/host/win/launch_process_with_token.h
index 678ade24ed2120..bc8157a300b169 100644
--- a/remoting/host/win/launch_process_with_token.h
+++ b/remoting/host/win/launch_process_with_token.h
@@ -65,7 +65,7 @@ bool CreateSessionToken(uint32 session_id, base::win::ScopedHandle* token_out);
 // The other parameters are passed directly to CreateProcessAsUser().
 // If |inherit_handles| is true |g_inherit_handles_lock| should be taken while
 // any inheritable handles are open.
-bool LaunchProcessWithToken(const FilePath& binary,
+bool LaunchProcessWithToken(const base::FilePath& binary,
                             const CommandLine::StringType& command_line,
                             HANDLE user_token,
                             SECURITY_ATTRIBUTES* process_attributes,
diff --git a/remoting/host/win/unprivileged_process_delegate.cc b/remoting/host/win/unprivileged_process_delegate.cc
index 6c2b740a2562bf..f5c1e76be537d2 100644
--- a/remoting/host/win/unprivileged_process_delegate.cc
+++ b/remoting/host/win/unprivileged_process_delegate.cc
@@ -222,7 +222,7 @@ bool CreateWindowStationAndDesktop(ScopedSid logon_sid,
 UnprivilegedProcessDelegate::UnprivilegedProcessDelegate(
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
-    const FilePath& binary_path)
+    const base::FilePath& binary_path)
     : main_task_runner_(main_task_runner),
       io_task_runner_(io_task_runner),
       binary_path_(binary_path) {
diff --git a/remoting/host/win/unprivileged_process_delegate.h b/remoting/host/win/unprivileged_process_delegate.h
index 06f6f9dee71743..d1da1d0abf7c19 100644
--- a/remoting/host/win/unprivileged_process_delegate.h
+++ b/remoting/host/win/unprivileged_process_delegate.h
@@ -31,7 +31,7 @@ class UnprivilegedProcessDelegate : public WorkerProcessLauncher::Delegate {
   UnprivilegedProcessDelegate(
       scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
-      const FilePath& binary_path);
+      const base::FilePath& binary_path);
   virtual ~UnprivilegedProcessDelegate();
 
   // IPC::Sender implementation.
@@ -53,7 +53,7 @@ class UnprivilegedProcessDelegate : public WorkerProcessLauncher::Delegate {
   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   // Path to the worker process binary.
-  FilePath binary_path_;
+  base::FilePath binary_path_;
 
   // The server end of the IPC channel used to communicate to the worker
   // process.
diff --git a/remoting/host/win/wts_console_session_process_driver.cc b/remoting/host/win/wts_console_session_process_driver.cc
index 1280ae852756e1..d321e135662443 100644
--- a/remoting/host/win/wts_console_session_process_driver.cc
+++ b/remoting/host/win/wts_console_session_process_driver.cc
@@ -82,7 +82,7 @@ void WtsConsoleSessionProcessDriver::OnSessionAttached(uint32 session_id) {
   DCHECK(launcher_.get() == NULL);
 
   // Construct the host binary name.
-  FilePath host_binary;
+  base::FilePath host_binary;
   if (!GetInstalledBinaryPath(kHostBinaryName, &host_binary)) {
     Stop();
     return;
diff --git a/remoting/host/win/wts_session_process_delegate.cc b/remoting/host/win/wts_session_process_delegate.cc
index 88ff519b3e89c3..8c7d552fe487f6 100644
--- a/remoting/host/win/wts_session_process_delegate.cc
+++ b/remoting/host/win/wts_session_process_delegate.cc
@@ -56,7 +56,7 @@ class WtsSessionProcessDelegate::Core
   // Stop() method has been called.
   Core(scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
        scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
-       const FilePath& binary_path,
+       const base::FilePath& binary_path,
        bool launch_elevated,
        const std::string& channel_security);
 
@@ -110,7 +110,7 @@ class WtsSessionProcessDelegate::Core
   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   // Path to the worker process binary.
-  FilePath binary_path_;
+  base::FilePath binary_path_;
 
   // The server end of the IPC channel used to communicate to the worker
   // process.
@@ -151,7 +151,7 @@ class WtsSessionProcessDelegate::Core
 WtsSessionProcessDelegate::Core::Core(
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
-    const FilePath& binary_path,
+    const base::FilePath& binary_path,
     bool launch_elevated,
     const std::string& channel_security)
     : main_task_runner_(main_task_runner),
@@ -249,7 +249,7 @@ bool WtsSessionProcessDelegate::Core::LaunchProcess(
     }
 
     // Construct the helper binary name.
-    FilePath daemon_binary;
+    base::FilePath daemon_binary;
     if (!GetInstalledBinaryPath(kDaemonBinaryName, &daemon_binary))
       return false;
 
@@ -485,7 +485,7 @@ void WtsSessionProcessDelegate::Core::OnJobNotification(DWORD message,
 WtsSessionProcessDelegate::WtsSessionProcessDelegate(
     scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
-    const FilePath& binary_path,
+    const base::FilePath& binary_path,
     uint32 session_id,
     bool launch_elevated,
     const std::string& channel_security) {
diff --git a/remoting/host/win/wts_session_process_delegate.h b/remoting/host/win/wts_session_process_delegate.h
index 13a12123f2c66d..5d55c98413017d 100644
--- a/remoting/host/win/wts_session_process_delegate.h
+++ b/remoting/host/win/wts_session_process_delegate.h
@@ -10,9 +10,8 @@
 #include "base/memory/ref_counted.h"
 #include "remoting/host/win/worker_process_launcher.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SingleThreadTaskRunner;
 } // namespace base
 
@@ -31,7 +30,7 @@ class WtsSessionProcessDelegate
   WtsSessionProcessDelegate(
       scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
-      const FilePath& binary_path,
+      const base::FilePath& binary_path,
       uint32 session_id,
       bool launch_elevated,
       const std::string& channel_security);
diff --git a/rlz/lib/recursive_cross_process_lock_posix.h b/rlz/lib/recursive_cross_process_lock_posix.h
index a39d473803c957..69a2c7a136b6e0 100644
--- a/rlz/lib/recursive_cross_process_lock_posix.h
+++ b/rlz/lib/recursive_cross_process_lock_posix.h
@@ -7,7 +7,9 @@
 
 #include <pthread.h>
 
+namespace base {
 class FilePath;
+}
 
 namespace rlz_lib {
 
@@ -20,7 +22,7 @@ struct RecursiveCrossProcessLock {
   // Tries to acquire a recursive cross-process lock. Note that this _always_
   // acquires the in-process lock (if it wasn't already acquired). The parent
   // directory of |lock_file| must exist.
-  bool TryGetCrossProcessLock(const FilePath& lock_filename);
+  bool TryGetCrossProcessLock(const base::FilePath& lock_filename);
 
   // Releases the lock. Should always be called, even if
   // TryGetCrossProcessLock() returned |false|.
diff --git a/rlz/lib/rlz_value_store.h b/rlz/lib/rlz_value_store.h
index 46e87df3331e75..4bd1f093b83af5 100644
--- a/rlz/lib/rlz_value_store.h
+++ b/rlz/lib/rlz_value_store.h
@@ -21,7 +21,9 @@
 #include <string>
 #include <vector>
 
+namespace base {
 class FilePath;
+}
 
 namespace rlz_lib {
 
@@ -106,7 +108,7 @@ class ScopedRlzValueStoreLock {
 #if defined(OS_POSIX)
 namespace testing {
 // Prefix |directory| to the path where the RLZ data file lives, for tests.
-void SetRlzStoreDirectory(const FilePath& directory);
+void SetRlzStoreDirectory(const base::FilePath& directory);
 
 // Returns the path of the file used as data store.
 std::string RlzStoreFilenameStr();
diff --git a/sql/connection.cc b/sql/connection.cc
index aefac60fac7e3f..5c0c15d7830fdf 100644
--- a/sql/connection.cc
+++ b/sql/connection.cc
@@ -128,7 +128,7 @@ Connection::~Connection() {
   Close();
 }
 
-bool Connection::Open(const FilePath& path) {
+bool Connection::Open(const base::FilePath& path) {
 #if defined(OS_WIN)
   return OpenInternal(WideToUTF8(path.value()));
 #elif defined(OS_POSIX)
diff --git a/sql/connection.h b/sql/connection.h
index 2722ffdc7f9d51..fa7c99da7c5eae 100644
--- a/sql/connection.h
+++ b/sql/connection.h
@@ -17,10 +17,13 @@
 #include "base/time.h"
 #include "sql/sql_export.h"
 
-class FilePath;
 struct sqlite3;
 struct sqlite3_stmt;
 
+namespace base {
+class FilePath;
+}
+
 namespace sql {
 
 class Statement;
@@ -154,7 +157,7 @@ class SQL_EXPORT Connection {
 
   // Initializes the SQL connection for the given file, returning true if the
   // file could be opened. You can call this or OpenInMemory.
-  bool Open(const FilePath& path) WARN_UNUSED_RESULT;
+  bool Open(const base::FilePath& path) WARN_UNUSED_RESULT;
 
   // Initializes the SQL connection for a temporary in-memory database. There
   // will be no associated file on disk, and the initial database will be
diff --git a/sql/connection_unittest.cc b/sql/connection_unittest.cc
index e8f454fa13493a..3ed2093cc4c1da 100644
--- a/sql/connection_unittest.cc
+++ b/sql/connection_unittest.cc
@@ -25,7 +25,7 @@ class SQLConnectionTest : public testing::Test {
 
   sql::Connection& db() { return db_; }
 
-  FilePath db_path() {
+  base::FilePath db_path() {
     return temp_dir_.path().AppendASCII("SQLConnectionTest.db");
   }
 
diff --git a/ui/aura/remote_root_window_host_win.h b/ui/aura/remote_root_window_host_win.h
index de69eb22b68907..05959a9afdbecc 100644
--- a/ui/aura/remote_root_window_host_win.h
+++ b/ui/aura/remote_root_window_host_win.h
@@ -14,7 +14,9 @@
 #include "ui/base/events/event_constants.h"
 #include "ui/gfx/native_widget_types.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace ui {
 class ViewProp;
@@ -27,20 +29,20 @@ class Sender;
 
 namespace aura {
 
-typedef base::Callback<void(const FilePath&, int, void*)>
+typedef base::Callback<void(const base::FilePath&, int, void*)>
     OpenFileCompletion;
 
-typedef base::Callback<void(const std::vector<FilePath>&, void*)>
+typedef base::Callback<void(const std::vector<base::FilePath>&, void*)>
     OpenMultipleFilesCompletion;
 
-typedef base::Callback<void(const FilePath&, int, void*)>
+typedef base::Callback<void(const base::FilePath&, int, void*)>
     SaveFileCompletion;
 
 // Handles the open file operation for Metro Chrome Ash. The callback passed in
 // is invoked when we receive the opened file name from the metro viewer.
 AURA_EXPORT void HandleOpenFile(
     const string16& title,
-    const FilePath& default_path,
+    const base::FilePath& default_path,
     const string16& filter,
     const OpenFileCompletion& callback);
 
@@ -49,7 +51,7 @@ AURA_EXPORT void HandleOpenFile(
 // viewer.
 AURA_EXPORT void HandleOpenMultipleFiles(
     const string16& title,
-    const FilePath& default_path,
+    const base::FilePath& default_path,
     const string16& filter,
     const OpenMultipleFilesCompletion& callback);
 
@@ -57,7 +59,7 @@ AURA_EXPORT void HandleOpenMultipleFiles(
 // is invoked when we receive the saved file name from the metro viewer.
 AURA_EXPORT void HandleSaveFile(
     const string16& title,
-    const FilePath& default_path,
+    const base::FilePath& default_path,
     const string16& filter,
     int filter_index,
     const string16& default_extension,
@@ -83,19 +85,19 @@ class AURA_EXPORT RemoteRootWindowHostWin : public RootWindowHost {
 
   void HandleOpenFile(
       const string16& title,
-      const FilePath& default_path,
+      const base::FilePath& default_path,
       const string16& filter,
       const OpenFileCompletion& callback);
 
   void HandleOpenMultipleFiles(
       const string16& title,
-      const FilePath& default_path,
+      const base::FilePath& default_path,
       const string16& filter,
       const OpenMultipleFilesCompletion& callback);
 
   void HandleSaveFile(
       const string16& title,
-      const FilePath& default_path,
+      const base::FilePath& default_path,
       const string16& filter,
       int filter_index,
       const string16& default_extension,
@@ -133,7 +135,7 @@ class AURA_EXPORT RemoteRootWindowHostWin : public RootWindowHost {
                         int filter_index);
   void OnFileOpenDone(bool success, string16 filename);
   void OnMultiFileOpenDone(bool success,
-                           const std::vector<FilePath>& files);
+                           const std::vector<base::FilePath>& files);
 
   // RootWindowHost overrides:
   virtual void SetDelegate(RootWindowHostDelegate* delegate) OVERRIDE;
diff --git a/ui/base/clipboard/clipboard.h b/ui/base/clipboard/clipboard.h
index 94d78712f26c6c..c85b90adcd2031 100644
--- a/ui/base/clipboard/clipboard.h
+++ b/ui/base/clipboard/clipboard.h
@@ -33,11 +33,14 @@
 #include "base/memory/scoped_ptr.h"
 #endif
 
+namespace base {
+class FilePath;
+}
+
 namespace gfx {
 class Size;
 }
 
-class FilePath;
 class SkBitmap;
 
 #if defined(TOOLKIT_GTK)
diff --git a/ui/base/dragdrop/download_file_interface.h b/ui/base/dragdrop/download_file_interface.h
index 62d4df0801e31f..a3bed252846a46 100644
--- a/ui/base/dragdrop/download_file_interface.h
+++ b/ui/base/dragdrop/download_file_interface.h
@@ -16,7 +16,9 @@
 #include <objidl.h>
 #endif
 
+namespace base {
 class FilePath;
+}
 
 namespace ui {
 
diff --git a/ui/base/resource/data_pack.h b/ui/base/resource/data_pack.h
index 08947af7b80a65..40913cb9788429 100644
--- a/ui/base/resource/data_pack.h
+++ b/ui/base/resource/data_pack.h
@@ -19,9 +19,8 @@
 #include "ui/base/resource/resource_handle.h"
 #include "ui/base/ui_export.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class RefCountedStaticMemory;
 }
 
@@ -37,7 +36,7 @@ class UI_EXPORT DataPack : public ResourceHandle {
   virtual ~DataPack();
 
   // Load a pack file from |path|, returning false on error.
-  bool LoadFromPath(const FilePath& path);
+  bool LoadFromPath(const base::FilePath& path);
 
   // Loads a pack file from |file|, returning false on error.
   bool LoadFromFile(base::PlatformFile file);
@@ -46,7 +45,7 @@ class UI_EXPORT DataPack : public ResourceHandle {
   // text resources to be written, their encoding must already agree to the
   // |textEncodingType| specified. If no text resources are present, please
   // indicate BINARY.
-  static bool WritePack(const FilePath& path,
+  static bool WritePack(const base::FilePath& path,
                         const std::map<uint16, base::StringPiece>& resources,
                         TextEncodingType textEncodingType);
 
diff --git a/ui/base/text/text_elider.h b/ui/base/text/text_elider.h
index a311caf47a4bab..a66845b4ba5df4 100644
--- a/ui/base/text/text_elider.h
+++ b/ui/base/text/text_elider.h
@@ -17,9 +17,12 @@
 #include "ui/base/ui_export.h"
 #include "ui/gfx/font.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace ui {
 
 UI_EXPORT extern const char kEllipsis[];
@@ -79,7 +82,7 @@ UI_EXPORT string16 ElideText(const string16& text,
 // filename is forced to have LTR directionality, which means that in RTL UI
 // the elided filename is wrapped with LRE (Left-To-Right Embedding) mark and
 // PDF (Pop Directional Formatting) mark.
-UI_EXPORT string16 ElideFilename(const FilePath& filename,
+UI_EXPORT string16 ElideFilename(const base::FilePath& filename,
                                  const gfx::Font& font,
                                  int available_pixel_width);
 
diff --git a/ui/base/win/shell.h b/ui/base/win/shell.h
index ada23de02a012e..3fd0dad09e8d90 100644
--- a/ui/base/win/shell.h
+++ b/ui/base/win/shell.h
@@ -10,7 +10,9 @@
 #include "base/string16.h"
 #include "ui/base/ui_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace ui {
 namespace win {
@@ -18,12 +20,12 @@ namespace win {
 // default application registered for the file specified by 'full_path',
 // ask the user, via the Windows "Open With" dialog.
 // Returns 'true' on successful open, 'false' otherwise.
-UI_EXPORT bool OpenItemViaShell(const FilePath& full_path);
+UI_EXPORT bool OpenItemViaShell(const base::FilePath& full_path);
 
 // The download manager now writes the alternate data stream with the
 // zone on all downloads. This function is equivalent to OpenItemViaShell
 // without showing the zone warning dialog.
-UI_EXPORT bool OpenItemViaShellNoZoneCheck(const FilePath& full_path);
+UI_EXPORT bool OpenItemViaShellNoZoneCheck(const base::FilePath& full_path);
 
 // Lower level function that allows opening of non-files like urls or GUIDs
 // don't use it if one of the above will do. |mask| is a valid combination
diff --git a/ui/gfx/icon_util.h b/ui/gfx/icon_util.h
index 4aa2676c71da4e..b48c0a52af7c15 100644
--- a/ui/gfx/icon_util.h
+++ b/ui/gfx/icon_util.h
@@ -16,10 +16,13 @@
 #include "ui/gfx/point.h"
 #include "ui/gfx/size.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace gfx {
 class Size;
 }
-class FilePath;
 class SkBitmap;
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -107,7 +110,7 @@ class UI_EXPORT IconUtil {
   // The function returns true on success and false otherwise.
   static bool CreateIconFileFromSkBitmap(const SkBitmap& bitmap,
                                          const SkBitmap& large_bitmap,
-                                         const FilePath& icon_path);
+                                         const base::FilePath& icon_path);
 
   // Creates a cursor of the specified size from the DIB passed in.
   // Returns the cursor on success or NULL on failure.
diff --git a/webkit/appcache/appcache_database.cc b/webkit/appcache/appcache_database.cc
index e8f4b0bb1e6073..95b430979fb3ab 100644
--- a/webkit/appcache/appcache_database.cc
+++ b/webkit/appcache/appcache_database.cc
@@ -177,7 +177,7 @@ AppCacheDatabase::NamespaceRecord::~NamespaceRecord() {
 }
 
 
-AppCacheDatabase::AppCacheDatabase(const FilePath& path)
+AppCacheDatabase::AppCacheDatabase(const base::FilePath& path)
     : db_file_path_(path), is_disabled_(false), is_recreating_(false) {
 }
 
@@ -1103,7 +1103,7 @@ bool AppCacheDatabase::DeleteExistingAndCreateNewDatabase() {
   ResetConnectionAndTables();
 
   // This also deletes the disk cache data.
-  FilePath directory = db_file_path_.DirName();
+  base::FilePath directory = db_file_path_.DirName();
   if (!file_util::Delete(directory, true) ||
       !file_util::CreateDirectory(directory)) {
     return false;
diff --git a/webkit/appcache/appcache_database.h b/webkit/appcache/appcache_database.h
index 5fe74a46659e64..b110ba190a87f7 100644
--- a/webkit/appcache/appcache_database.h
+++ b/webkit/appcache/appcache_database.h
@@ -81,7 +81,7 @@ class WEBKIT_STORAGE_EXPORT AppCacheDatabase {
     GURL namespace_url;
   };
 
-  explicit AppCacheDatabase(const FilePath& path);
+  explicit AppCacheDatabase(const base::FilePath& path);
   ~AppCacheDatabase();
 
   void CloseConnection();
@@ -200,7 +200,7 @@ class WEBKIT_STORAGE_EXPORT AppCacheDatabase {
   // and bodies are stored, and then creates a new database file.
   bool DeleteExistingAndCreateNewDatabase();
 
-  FilePath db_file_path_;
+  base::FilePath db_file_path_;
   scoped_ptr<sql::Connection> db_;
   scoped_ptr<sql::MetaTable> meta_table_;
   bool is_disabled_;
diff --git a/webkit/appcache/appcache_database_unittest.cc b/webkit/appcache/appcache_database_unittest.cc
index d84d4518705294..4c7affba236c33 100644
--- a/webkit/appcache/appcache_database_unittest.cc
+++ b/webkit/appcache/appcache_database_unittest.cc
@@ -41,7 +41,7 @@ class AppCacheDatabaseTest {};
 
 TEST(AppCacheDatabaseTest, LazyOpen) {
   // Use an empty file path to use an in-memory sqlite database.
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
 
   EXPECT_FALSE(db.LazyOpen(false));
@@ -65,9 +65,9 @@ TEST(AppCacheDatabaseTest, ReCreate) {
   // Real files on disk for this test.
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = temp_dir.path().AppendASCII("appcache.db");
-  const FilePath kNestedDir = temp_dir.path().AppendASCII("nested");
-  const FilePath kOtherFile =  kNestedDir.AppendASCII("other_file");
+  const base::FilePath kDbFile = temp_dir.path().AppendASCII("appcache.db");
+  const base::FilePath kNestedDir = temp_dir.path().AppendASCII("nested");
+  const base::FilePath kOtherFile =  kNestedDir.AppendASCII("other_file");
   EXPECT_TRUE(file_util::CreateDirectory(kNestedDir));
   EXPECT_EQ(3, file_util::WriteFile(kOtherFile, "foo", 3));
 
@@ -87,7 +87,7 @@ TEST(AppCacheDatabaseTest, ReCreate) {
 }
 
 TEST(AppCacheDatabaseTest, EntryRecords) {
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -161,7 +161,7 @@ TEST(AppCacheDatabaseTest, EntryRecords) {
 }
 
 TEST(AppCacheDatabaseTest, CacheRecords) {
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -203,7 +203,7 @@ TEST(AppCacheDatabaseTest, CacheRecords) {
 }
 
 TEST(AppCacheDatabaseTest, GroupRecords) {
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -330,7 +330,7 @@ TEST(AppCacheDatabaseTest, GroupRecords) {
 }
 
 TEST(AppCacheDatabaseTest, NamespaceRecords) {
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -430,7 +430,7 @@ TEST(AppCacheDatabaseTest, NamespaceRecords) {
 }
 
 TEST(AppCacheDatabaseTest, OnlineWhiteListRecords) {
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -476,7 +476,7 @@ TEST(AppCacheDatabaseTest, OnlineWhiteListRecords) {
 }
 
 TEST(AppCacheDatabaseTest, DeletableResponseIds) {
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -552,7 +552,7 @@ TEST(AppCacheDatabaseTest, OriginUsage) {
   const GURL kOtherOriginManifestUrl("http://other/manifest");
   const GURL kOtherOrigin(kOtherOriginManifestUrl.GetOrigin());
 
-  const FilePath kEmptyPath;
+  const base::FilePath kEmptyPath;
   AppCacheDatabase db(kEmptyPath);
   EXPECT_TRUE(db.LazyOpen(true));
 
@@ -621,7 +621,7 @@ TEST(AppCacheDatabaseTest, UpgradeSchema3to4) {
   // Real file on disk for this test.
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = temp_dir.path().AppendASCII("upgrade.db");
+  const base::FilePath kDbFile = temp_dir.path().AppendASCII("upgrade.db");
 
   const GURL kMockOrigin("http://mockorigin/");
   const char kNamespaceUrlFormat[] = "namespace%d";
diff --git a/webkit/appcache/appcache_disk_cache.cc b/webkit/appcache/appcache_disk_cache.cc
index 88bea87fa0c31e..7b8e699ed8bd37 100644
--- a/webkit/appcache/appcache_disk_cache.cc
+++ b/webkit/appcache/appcache_disk_cache.cc
@@ -164,7 +164,7 @@ AppCacheDiskCache::~AppCacheDiskCache() {
 }
 
 int AppCacheDiskCache::InitWithDiskBackend(
-    const FilePath& disk_cache_directory, int disk_cache_size, bool force,
+    const base::FilePath& disk_cache_directory, int disk_cache_size, bool force,
     base::MessageLoopProxy* cache_thread,
     const net::CompletionCallback& callback) {
   return Init(net::APP_CACHE, disk_cache_directory,
@@ -173,7 +173,7 @@ int AppCacheDiskCache::InitWithDiskBackend(
 
 int AppCacheDiskCache::InitWithMemBackend(
     int mem_cache_size, const net::CompletionCallback& callback) {
-  return Init(net::MEMORY_CACHE, FilePath(), mem_cache_size, false, NULL,
+  return Init(net::MEMORY_CACHE, base::FilePath(), mem_cache_size, false, NULL,
               callback);
 }
 
@@ -262,7 +262,7 @@ AppCacheDiskCache::PendingCall::PendingCall(PendingCallType call_type,
 AppCacheDiskCache::PendingCall::~PendingCall() {}
 
 int AppCacheDiskCache::Init(net::CacheType cache_type,
-                            const FilePath& cache_directory,
+                            const base::FilePath& cache_directory,
                             int cache_size, bool force,
                             base::MessageLoopProxy* cache_thread,
                             const net::CompletionCallback& callback) {
diff --git a/webkit/appcache/appcache_disk_cache.h b/webkit/appcache/appcache_disk_cache.h
index 529db976196cf9..aafc84689e88cd 100644
--- a/webkit/appcache/appcache_disk_cache.h
+++ b/webkit/appcache/appcache_disk_cache.h
@@ -24,7 +24,7 @@ class WEBKIT_STORAGE_EXPORT AppCacheDiskCache
   virtual ~AppCacheDiskCache();
 
   // Initializes the object to use disk backed storage.
-  int InitWithDiskBackend(const FilePath& disk_cache_directory,
+  int InitWithDiskBackend(const base::FilePath& disk_cache_directory,
                           int disk_cache_size, bool force,
                           base::MessageLoopProxy* cache_thread,
                           const net::CompletionCallback& callback);
@@ -80,7 +80,7 @@ class WEBKIT_STORAGE_EXPORT AppCacheDiskCache
     return create_backend_callback_.get() != NULL;
   }
   disk_cache::Backend* disk_cache() { return disk_cache_.get(); }
-  int Init(net::CacheType cache_type, const FilePath& directory,
+  int Init(net::CacheType cache_type, const base::FilePath& directory,
            int cache_size, bool force, base::MessageLoopProxy* cache_thread,
            const net::CompletionCallback& callback);
   void OnCreateBackendComplete(int rv);
diff --git a/webkit/appcache/appcache_interfaces.cc b/webkit/appcache/appcache_interfaces.cc
index 70de5ffad06edd..3f3d1d70a50f61 100644
--- a/webkit/appcache/appcache_interfaces.cc
+++ b/webkit/appcache/appcache_interfaces.cc
@@ -19,7 +19,8 @@ const char kHttpsScheme[] = "https";
 const char kHttpGETMethod[] = "GET";
 const char kHttpHEADMethod[] = "HEAD";
 
-const FilePath::CharType kAppCacheDatabaseName[] = FILE_PATH_LITERAL("Index");
+const base::FilePath::CharType kAppCacheDatabaseName[] =
+    FILE_PATH_LITERAL("Index");
 
 AppCacheInfo::AppCacheInfo()
     : cache_id(kNoCacheId),
diff --git a/webkit/appcache/appcache_interfaces.h b/webkit/appcache/appcache_interfaces.h
index ed1dee79708a13..78752b1df1d800 100644
--- a/webkit/appcache/appcache_interfaces.h
+++ b/webkit/appcache/appcache_interfaces.h
@@ -169,7 +169,8 @@ bool IsSchemeSupported(const GURL& url);
 bool IsMethodSupported(const std::string& method);
 bool IsSchemeAndMethodSupported(const net::URLRequest* request);
 
-WEBKIT_STORAGE_EXPORT extern const FilePath::CharType kAppCacheDatabaseName[];
+WEBKIT_STORAGE_EXPORT extern const base::FilePath::CharType
+    kAppCacheDatabaseName[];
 
 }  // namespace
 
diff --git a/webkit/appcache/appcache_service.cc b/webkit/appcache/appcache_service.cc
index 0149e62a02961c..c455436da88e55 100644
--- a/webkit/appcache/appcache_service.cc
+++ b/webkit/appcache/appcache_service.cc
@@ -449,7 +449,7 @@ AppCacheService::~AppCacheService() {
   storage_.reset();
 }
 
-void AppCacheService::Initialize(const FilePath& cache_directory,
+void AppCacheService::Initialize(const base::FilePath& cache_directory,
                                  base::MessageLoopProxy* db_thread,
                                  base::MessageLoopProxy* cache_thread) {
   DCHECK(!storage_.get());
diff --git a/webkit/appcache/appcache_service.h b/webkit/appcache/appcache_service.h
index dfc7302999fe64..3a4003dcc90a1f 100644
--- a/webkit/appcache/appcache_service.h
+++ b/webkit/appcache/appcache_service.h
@@ -17,13 +17,12 @@
 #include "webkit/appcache/appcache_storage.h"
 #include "webkit/storage/webkit_storage_export.h"
 
-class FilePath;
-
 namespace net {
 class URLRequestContext;
 }  // namespace net
 
 namespace base {
+class FilePath;
 class MessageLoopProxy;
 }
 
@@ -59,7 +58,7 @@ class WEBKIT_STORAGE_EXPORT AppCacheService {
   explicit AppCacheService(quota::QuotaManagerProxy* quota_manager_proxy);
   virtual ~AppCacheService();
 
-  void Initialize(const FilePath& cache_directory,
+  void Initialize(const base::FilePath& cache_directory,
                   base::MessageLoopProxy* db_thread,
                   base::MessageLoopProxy* cache_thread);
 
diff --git a/webkit/appcache/appcache_storage_impl.cc b/webkit/appcache/appcache_storage_impl.cc
index 89b196b9606385..5c332098fd65f6 100644
--- a/webkit/appcache/appcache_storage_impl.cc
+++ b/webkit/appcache/appcache_storage_impl.cc
@@ -39,7 +39,7 @@ static const int kDefaultQuota = 5 * 1024 * 1024;
 
 static const int kMaxDiskCacheSize = 250 * 1024 * 1024;
 static const int kMaxMemDiskCacheSize = 10 * 1024 * 1024;
-static const FilePath::CharType kDiskCacheDirectoryName[] =
+static const base::FilePath::CharType kDiskCacheDirectoryName[] =
     FILE_PATH_LITERAL("Cache");
 
 namespace {
@@ -1312,7 +1312,7 @@ AppCacheStorageImpl::~AppCacheStorageImpl() {
   }
 }
 
-void AppCacheStorageImpl::Initialize(const FilePath& cache_directory,
+void AppCacheStorageImpl::Initialize(const base::FilePath& cache_directory,
                                      base::MessageLoopProxy* db_thread,
                                      base::MessageLoopProxy* cache_thread) {
   DCHECK(db_thread);
@@ -1320,7 +1320,7 @@ void AppCacheStorageImpl::Initialize(const FilePath& cache_directory,
   cache_directory_ = cache_directory;
   is_incognito_ = cache_directory_.empty();
 
-  FilePath db_file_path;
+  base::FilePath db_file_path;
   if (!is_incognito_)
     db_file_path = cache_directory_.Append(kAppCacheDatabaseName);
   database_ = new AppCacheDatabase(db_file_path);
diff --git a/webkit/appcache/appcache_storage_impl.h b/webkit/appcache/appcache_storage_impl.h
index 7441f4ff6a4158..4211e62cc19d8d 100644
--- a/webkit/appcache/appcache_storage_impl.h
+++ b/webkit/appcache/appcache_storage_impl.h
@@ -31,7 +31,7 @@ class AppCacheStorageImpl : public AppCacheStorage {
   explicit AppCacheStorageImpl(AppCacheService* service);
   virtual ~AppCacheStorageImpl();
 
-  void Initialize(const FilePath& cache_directory,
+  void Initialize(const base::FilePath& cache_directory,
                   base::MessageLoopProxy* db_thread,
                   base::MessageLoopProxy* cache_thread);
   void Disable();
@@ -134,7 +134,7 @@ class AppCacheStorageImpl : public AppCacheStorage {
   WEBKIT_STORAGE_EXPORT AppCacheDiskCache* disk_cache();
 
   // The directory in which we place files in the file system.
-  FilePath cache_directory_;
+  base::FilePath cache_directory_;
   bool is_incognito_;
 
   // This class operates primarily on the IO thread, but schedules
diff --git a/webkit/appcache/appcache_storage_impl_unittest.cc b/webkit/appcache/appcache_storage_impl_unittest.cc
index c8b86e5766bab8..37ed315087620a 100644
--- a/webkit/appcache/appcache_storage_impl_unittest.cc
+++ b/webkit/appcache/appcache_storage_impl_unittest.cc
@@ -132,7 +132,7 @@ class AppCacheStorageImplTest : public testing::Test {
   class MockQuotaManager : public quota::QuotaManager {
    public:
     MockQuotaManager()
-      : QuotaManager(true /* is_incognito */, FilePath(),
+      : QuotaManager(true /* is_incognito */, base::FilePath(),
                      io_thread->message_loop_proxy(),
                      db_thread->message_loop_proxy(),
                      NULL),
@@ -261,7 +261,7 @@ class AppCacheStorageImplTest : public testing::Test {
   void SetUpTest() {
     DCHECK(MessageLoop::current() == io_thread->message_loop());
     service_.reset(new AppCacheService(NULL));
-    service_->Initialize(FilePath(), db_thread->message_loop_proxy(), NULL);
+    service_->Initialize(base::FilePath(), db_thread->message_loop_proxy(), NULL);
     mock_quota_manager_proxy_ = new MockQuotaManagerProxy();
     service_->quota_manager_proxy_ = mock_quota_manager_proxy_;
     delegate_.reset(new MockStorageDelegate(this));
diff --git a/webkit/base/data_element.cc b/webkit/base/data_element.cc
index a514ac556da6d8..472a88b249bf05 100644
--- a/webkit/base/data_element.cc
+++ b/webkit/base/data_element.cc
@@ -16,7 +16,7 @@ DataElement::DataElement()
 DataElement::~DataElement() {}
 
 void DataElement::SetToFilePathRange(
-    const FilePath& path,
+    const base::FilePath& path,
     uint64 offset, uint64 length,
     const base::Time& expected_modification_time) {
   type_ = TYPE_FILE;
diff --git a/webkit/base/data_element.h b/webkit/base/data_element.h
index 4a5c7268dc7b5d..3e286baa743b69 100644
--- a/webkit/base/data_element.h
+++ b/webkit/base/data_element.h
@@ -33,7 +33,7 @@ class WEBKIT_BASE_EXPORT DataElement {
 
   Type type() const { return type_; }
   const char* bytes() const { return bytes_ ? bytes_ : &buf_[0]; }
-  const FilePath& path() const { return path_; }
+  const base::FilePath& path() const { return path_; }
   const GURL& url() const { return url_; }
   uint64 offset() const { return offset_; }
   uint64 length() const { return length_; }
@@ -57,7 +57,7 @@ class WEBKIT_BASE_EXPORT DataElement {
   }
 
   // Sets TYPE_FILE data.
-  void SetToFilePath(const FilePath& path) {
+  void SetToFilePath(const base::FilePath& path) {
     SetToFilePathRange(path, 0, kuint64max, base::Time());
   }
 
@@ -67,7 +67,7 @@ class WEBKIT_BASE_EXPORT DataElement {
   }
 
   // Sets TYPE_FILE data with range.
-  void SetToFilePathRange(const FilePath& path,
+  void SetToFilePathRange(const base::FilePath& path,
                           uint64 offset, uint64 length,
                           const base::Time& expected_modification_time);
 
@@ -84,7 +84,7 @@ class WEBKIT_BASE_EXPORT DataElement {
   Type type_;
   std::vector<char> buf_;  // For TYPE_BYTES.
   const char* bytes_;  // For TYPE_BYTES.
-  FilePath path_;  // For TYPE_FILE.
+  base::FilePath path_;  // For TYPE_FILE.
   GURL url_;  // For TYPE_BLOB or TYPE_FILE_FILESYSTEM.
   uint64 offset_;
   uint64 length_;
diff --git a/webkit/base/file_path_string_conversions.cc b/webkit/base/file_path_string_conversions.cc
index 3ff7557fa318bd..566c8bb9dedd12 100644
--- a/webkit/base/file_path_string_conversions.cc
+++ b/webkit/base/file_path_string_conversions.cc
@@ -10,7 +10,8 @@
 
 namespace webkit_base {
 
-FilePath::StringType WebStringToFilePathString(const WebKit::WebString& str) {
+base::FilePath::StringType WebStringToFilePathString(
+    const WebKit::WebString& str) {
 #if defined(OS_POSIX)
   return base::SysWideToNativeMB(UTF16ToWideHack(str));
 #elif defined(OS_WIN)
@@ -18,7 +19,8 @@ FilePath::StringType WebStringToFilePathString(const WebKit::WebString& str) {
 #endif
 }
 
-WebKit::WebString FilePathStringToWebString(const FilePath::StringType& str) {
+WebKit::WebString FilePathStringToWebString(
+    const base::FilePath::StringType& str) {
 #if defined(OS_POSIX)
   return WideToUTF16Hack(base::SysNativeMBToWide(str));
 #elif defined(OS_WIN)
@@ -26,11 +28,11 @@ WebKit::WebString FilePathStringToWebString(const FilePath::StringType& str) {
 #endif
 }
 
-FilePath WebStringToFilePath(const WebKit::WebString& str) {
-  return FilePath(WebStringToFilePathString(str));
+base::FilePath WebStringToFilePath(const WebKit::WebString& str) {
+  return base::FilePath(WebStringToFilePathString(str));
 }
 
-WebKit::WebString FilePathToWebString(const FilePath& file_path) {
+WebKit::WebString FilePathToWebString(const base::FilePath& file_path) {
   return FilePathStringToWebString(file_path.value());
 }
 
diff --git a/webkit/base/file_path_string_conversions.h b/webkit/base/file_path_string_conversions.h
index 902a88194389aa..951c466f854ce1 100644
--- a/webkit/base/file_path_string_conversions.h
+++ b/webkit/base/file_path_string_conversions.h
@@ -14,13 +14,13 @@ class WebString;
 
 namespace webkit_base {
 
-WEBKIT_BASE_EXPORT FilePath::StringType WebStringToFilePathString(
+WEBKIT_BASE_EXPORT base::FilePath::StringType WebStringToFilePathString(
     const WebKit::WebString& str);
 WEBKIT_BASE_EXPORT WebKit::WebString FilePathStringToWebString(
-    const FilePath::StringType& str);
-WEBKIT_BASE_EXPORT FilePath WebStringToFilePath(const WebKit::WebString& str);
+    const base::FilePath::StringType& str);
+WEBKIT_BASE_EXPORT base::FilePath WebStringToFilePath(const WebKit::WebString& str);
 WEBKIT_BASE_EXPORT WebKit::WebString FilePathToWebString(
-    const FilePath& file_path);
+    const base::FilePath& file_path);
 
 }  // namespace webkit_base
 
diff --git a/webkit/blob/blob_data.cc b/webkit/blob/blob_data.cc
index 2f62e32f04e374..4a2ab8633eec5d 100644
--- a/webkit/blob/blob_data.cc
+++ b/webkit/blob/blob_data.cc
@@ -21,7 +21,7 @@ void BlobData::AppendData(const char* data, size_t length) {
   items_.back().SetToBytes(data, length);
 }
 
-void BlobData::AppendFile(const FilePath& file_path,
+void BlobData::AppendFile(const base::FilePath& file_path,
                           uint64 offset, uint64 length,
                           const base::Time& expected_modification_time) {
   DCHECK(length > 0);
diff --git a/webkit/blob/blob_data.h b/webkit/blob/blob_data.h
index 45c75ca5a09f6c..08c47f4862fc68 100644
--- a/webkit/blob/blob_data.h
+++ b/webkit/blob/blob_data.h
@@ -30,7 +30,7 @@ class WEBKIT_STORAGE_EXPORT BlobData : public base::RefCounted<BlobData> {
 
   void AppendData(const char* data, size_t length);
 
-  void AppendFile(const FilePath& file_path, uint64 offset, uint64 length,
+  void AppendFile(const base::FilePath& file_path, uint64 offset, uint64 length,
                   const base::Time& expected_modification_time);
 
   void AppendBlob(const GURL& blob_url, uint64 offset, uint64 length);
diff --git a/webkit/blob/blob_storage_controller.cc b/webkit/blob/blob_storage_controller.cc
index 503c47ea995717..8649d98f5dd466 100644
--- a/webkit/blob/blob_storage_controller.cc
+++ b/webkit/blob/blob_storage_controller.cc
@@ -215,7 +215,7 @@ void BlobStorageController::AppendStorageItems(
 
 void BlobStorageController::AppendFileItem(
     BlobData* target_blob_data,
-    const FilePath& file_path, uint64 offset, uint64 length,
+    const base::FilePath& file_path, uint64 offset, uint64 length,
     const base::Time& expected_modification_time) {
   target_blob_data->AppendFile(file_path, offset, length,
                                expected_modification_time);
diff --git a/webkit/blob/blob_storage_controller.h b/webkit/blob/blob_storage_controller.h
index c7e7631e003c65..a0c72b24070c2e 100644
--- a/webkit/blob/blob_storage_controller.h
+++ b/webkit/blob/blob_storage_controller.h
@@ -15,9 +15,9 @@
 #include "webkit/storage/webkit_storage_export.h"
 
 class GURL;
-class FilePath;
 
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -48,7 +48,8 @@ class WEBKIT_STORAGE_EXPORT BlobStorageController {
                           uint64 offset,
                           uint64 length);
   void AppendFileItem(BlobData* target_blob_data,
-                      const FilePath& file_path, uint64 offset, uint64 length,
+                      const base::FilePath& file_path, uint64 offset,
+                      uint64 length,
                       const base::Time& expected_modification_time);
   void AppendFileSystemFileItem(
       BlobData* target_blob_data,
diff --git a/webkit/blob/blob_url_request_job_unittest.cc b/webkit/blob/blob_url_request_job_unittest.cc
index 007d9360e77abf..8b07a4f08f0d50 100644
--- a/webkit/blob/blob_url_request_job_unittest.cc
+++ b/webkit/blob/blob_url_request_job_unittest.cc
@@ -209,7 +209,7 @@ class BlobURLRequestJobTest : public testing::Test {
         file_system_context_->CreateCrackedFileSystemURL(
             GURL(kFileSystemURLOrigin),
             kFileSystemType,
-            FilePath().AppendASCII(filename));
+            base::FilePath().AppendASCII(filename));
 
     fileapi::FileSystemFileUtil* file_util =
         file_system_context_->GetFileUtil(kFileSystemType);
@@ -232,7 +232,7 @@ class BlobURLRequestJobTest : public testing::Test {
     base::ClosePlatformFile(handle);
 
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util->GetFileInfo(&context, url, &file_info,
                                      &platform_path));
@@ -297,8 +297,8 @@ class BlobURLRequestJobTest : public testing::Test {
 
  protected:
   base::ScopedTempDir temp_dir_;
-  FilePath temp_file1_;
-  FilePath temp_file2_;
+  base::FilePath temp_file1_;
+  base::FilePath temp_file2_;
   base::Time temp_file_modification_time1_;
   base::Time temp_file_modification_time2_;
   GURL file_system_root_url_;
@@ -330,7 +330,7 @@ TEST_F(BlobURLRequestJobTest, TestGetSimpleFileRequest) {
 }
 
 TEST_F(BlobURLRequestJobTest, TestGetLargeFileRequest) {
-  FilePath large_temp_file = temp_dir_.path().AppendASCII("LargeBlob.dat");
+  base::FilePath large_temp_file = temp_dir_.path().AppendASCII("LargeBlob.dat");
   std::string large_data;
   large_data.reserve(kBufferSize * 5);
   for (int i = 0; i < kBufferSize * 5; ++i)
@@ -343,7 +343,7 @@ TEST_F(BlobURLRequestJobTest, TestGetLargeFileRequest) {
 }
 
 TEST_F(BlobURLRequestJobTest, TestGetNonExistentFileRequest) {
-  FilePath non_existent_file =
+  base::FilePath non_existent_file =
       temp_file1_.InsertBeforeExtension(FILE_PATH_LITERAL("-na"));
   blob_data_->AppendFile(non_existent_file, 0, -1, base::Time());
   TestErrorRequest(404);
diff --git a/webkit/blob/local_file_stream_reader.cc b/webkit/blob/local_file_stream_reader.cc
index aa077efc45e88f..dab8aa5dea6889 100644
--- a/webkit/blob/local_file_stream_reader.cc
+++ b/webkit/blob/local_file_stream_reader.cc
@@ -34,7 +34,7 @@ bool VerifySnapshotTime(const base::Time& expected_modification_time,
 
 LocalFileStreamReader::LocalFileStreamReader(
     base::TaskRunner* task_runner,
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int64 initial_offset,
     const base::Time& expected_modification_time)
     : task_runner_(task_runner),
diff --git a/webkit/blob/local_file_stream_reader.h b/webkit/blob/local_file_stream_reader.h
index 55b70bf8b7e15e..de1f64e9931346 100644
--- a/webkit/blob/local_file_stream_reader.h
+++ b/webkit/blob/local_file_stream_reader.h
@@ -39,7 +39,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileStreamReader : public FileStreamReader {
   // it does any succeeding read operations should fail with
   // ERR_UPLOAD_FILE_CHANGED error.
   LocalFileStreamReader(base::TaskRunner* task_runner,
-                        const FilePath& file_path,
+                        const base::FilePath& file_path,
                         int64 initial_offset,
                    const base::Time& expected_modification_time);
   virtual ~LocalFileStreamReader();
@@ -71,7 +71,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileStreamReader : public FileStreamReader {
 
   scoped_refptr<base::TaskRunner> task_runner_;
   scoped_ptr<net::FileStream> stream_impl_;
-  const FilePath file_path_;
+  const base::FilePath file_path_;
   const int64 initial_offset_;
   const base::Time expected_modification_time_;
   bool has_pending_open_;
diff --git a/webkit/blob/local_file_stream_reader_unittest.cc b/webkit/blob/local_file_stream_reader_unittest.cc
index 3aaf0050f7a9a7..fa959b3ba1b27f 100644
--- a/webkit/blob/local_file_stream_reader_unittest.cc
+++ b/webkit/blob/local_file_stream_reader_unittest.cc
@@ -81,7 +81,7 @@ class LocalFileStreamReaderTest : public testing::Test {
 
  protected:
   LocalFileStreamReader* CreateFileReader(
-      const FilePath& path,
+      const base::FilePath& path,
       int64 initial_offset,
       const base::Time& expected_modification_time) {
     return new LocalFileStreamReader(
@@ -103,8 +103,8 @@ class LocalFileStreamReaderTest : public testing::Test {
     return file_thread_.message_loop_proxy().get();
   }
 
-  FilePath test_dir() const { return dir_.path(); }
-  FilePath test_path() const { return dir_.path().AppendASCII("test"); }
+  base::FilePath test_dir() const { return dir_.path(); }
+  base::FilePath test_path() const { return dir_.path().AppendASCII("test"); }
   base::Time test_file_modification_time() const {
     return test_file_modification_time_;
   }
@@ -123,7 +123,7 @@ class LocalFileStreamReaderTest : public testing::Test {
 };
 
 TEST_F(LocalFileStreamReaderTest, NonExistent) {
-  FilePath nonexistent_path = test_dir().AppendASCII("nonexistent");
+  base::FilePath nonexistent_path = test_dir().AppendASCII("nonexistent");
   scoped_ptr<LocalFileStreamReader> reader(
       CreateFileReader(nonexistent_path, 0, base::Time()));
   int result = 0;
@@ -134,7 +134,7 @@ TEST_F(LocalFileStreamReaderTest, NonExistent) {
 }
 
 TEST_F(LocalFileStreamReaderTest, Empty) {
-  FilePath empty_path = test_dir().AppendASCII("empty");
+  base::FilePath empty_path = test_dir().AppendASCII("empty");
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
   base::PlatformFile file = base::CreatePlatformFile(
       empty_path,
diff --git a/webkit/blob/shareable_file_reference.cc b/webkit/blob/shareable_file_reference.cc
index f85b97e1c3936f..07acac3a55e559 100644
--- a/webkit/blob/shareable_file_reference.cc
+++ b/webkit/blob/shareable_file_reference.cc
@@ -23,7 +23,7 @@ namespace {
 // check thread in the dtor.
 class ShareableFileMap {
  public:
-  typedef std::map<FilePath, ShareableFileReference*> FileMap;
+  typedef std::map<base::FilePath, ShareableFileReference*> FileMap;
   typedef FileMap::iterator iterator;
   typedef FileMap::key_type key_type;
   typedef FileMap::value_type value_type;
@@ -66,7 +66,7 @@ base::LazyInstance<ShareableFileMap> g_file_map = LAZY_INSTANCE_INITIALIZER;
 
 // static
 scoped_refptr<ShareableFileReference> ShareableFileReference::Get(
-    const FilePath& path) {
+    const base::FilePath& path) {
   ShareableFileMap::iterator found = g_file_map.Get().Find(path);
   ShareableFileReference* reference =
       (found == g_file_map.Get().End()) ? NULL : found->second;
@@ -75,7 +75,7 @@ scoped_refptr<ShareableFileReference> ShareableFileReference::Get(
 
 // static
 scoped_refptr<ShareableFileReference> ShareableFileReference::GetOrCreate(
-    const FilePath& path, FinalReleasePolicy policy,
+    const base::FilePath& path, FinalReleasePolicy policy,
     base::TaskRunner* file_task_runner) {
   DCHECK(file_task_runner);
   typedef std::pair<ShareableFileMap::iterator, bool> InsertResult;
@@ -101,7 +101,7 @@ void ShareableFileReference::AddFinalReleaseCallback(
 }
 
 ShareableFileReference::ShareableFileReference(
-    const FilePath& path, FinalReleasePolicy policy,
+    const base::FilePath& path, FinalReleasePolicy policy,
     base::TaskRunner* file_task_runner)
     : path_(path),
       final_release_policy_(policy),
diff --git a/webkit/blob/shareable_file_reference.h b/webkit/blob/shareable_file_reference.h
index 14405861c2e26b..5323cfa85f928e 100644
--- a/webkit/blob/shareable_file_reference.h
+++ b/webkit/blob/shareable_file_reference.h
@@ -25,7 +25,7 @@ namespace webkit_blob {
 class WEBKIT_STORAGE_EXPORT ShareableFileReference
     : public base::RefCounted<ShareableFileReference> {
  public:
-  typedef base::Callback<void(const FilePath&)> FinalReleaseCallback;
+  typedef base::Callback<void(const base::FilePath&)> FinalReleaseCallback;
 
   enum FinalReleasePolicy {
     DELETE_ON_FINAL_RELEASE,
@@ -34,18 +34,18 @@ class WEBKIT_STORAGE_EXPORT ShareableFileReference
 
   // Returns a ShareableFileReference for the given path, if no reference
   // for this path exists returns NULL.
-  static scoped_refptr<ShareableFileReference> Get(const FilePath& path);
+  static scoped_refptr<ShareableFileReference> Get(const base::FilePath& path);
 
   // Returns a ShareableFileReference for the given path, creating a new
   // reference if none yet exists. If there's a pre-existing reference for
   // the path, the deletable parameter of this method is ignored.
   static scoped_refptr<ShareableFileReference> GetOrCreate(
-      const FilePath& path,
+      const base::FilePath& path,
       FinalReleasePolicy policy,
       base::TaskRunner* file_task_runner);
 
   // The full file path.
-  const FilePath& path() const { return path_; }
+  const base::FilePath& path() const { return path_; }
 
   // Whether it's to be deleted on final release.
   FinalReleasePolicy final_release_policy() const {
@@ -58,12 +58,12 @@ class WEBKIT_STORAGE_EXPORT ShareableFileReference
   friend class base::RefCounted<ShareableFileReference>;
 
   ShareableFileReference(
-      const FilePath& path,
+      const base::FilePath& path,
       FinalReleasePolicy policy,
       base::TaskRunner* file_task_runner);
   ~ShareableFileReference();
 
-  const FilePath path_;
+  const base::FilePath path_;
   const FinalReleasePolicy final_release_policy_;
   const scoped_refptr<base::TaskRunner> file_task_runner_;
   std::vector<FinalReleaseCallback> final_release_callbacks_;
diff --git a/webkit/blob/shareable_file_reference_unittest.cc b/webkit/blob/shareable_file_reference_unittest.cc
index d75a1bed8bbefc..15b6eb12655568 100644
--- a/webkit/blob/shareable_file_reference_unittest.cc
+++ b/webkit/blob/shareable_file_reference_unittest.cc
@@ -20,7 +20,7 @@ TEST(ShareableFileReferenceTest, TestReferences) {
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 
   // Create a file.
-  FilePath file;
+  base::FilePath file;
   file_util::CreateTemporaryFileInDir(temp_dir.path(), &file);
   EXPECT_TRUE(file_util::PathExists(file));
 
diff --git a/webkit/chromeos/fileapi/cros_mount_point_provider.cc b/webkit/chromeos/fileapi/cros_mount_point_provider.cc
index 5c801488c65e42..a90fcfaa6ecd87 100644
--- a/webkit/chromeos/fileapi/cros_mount_point_provider.cc
+++ b/webkit/chromeos/fileapi/cros_mount_point_provider.cc
@@ -72,18 +72,18 @@ void CrosMountPointProvider::ValidateFileSystemRoot(
   callback.Run(base::PLATFORM_FILE_OK);
 }
 
-FilePath CrosMountPointProvider::GetFileSystemRootPathOnFileThread(
+base::FilePath CrosMountPointProvider::GetFileSystemRootPathOnFileThread(
     const fileapi::FileSystemURL& url,
     bool create) {
   DCHECK(fileapi::IsolatedContext::IsIsolatedType(url.mount_type()));
   if (!url.is_valid())
-    return FilePath();
+    return base::FilePath();
 
-  FilePath root_path;
+  base::FilePath root_path;
   std::string mount_name = url.filesystem_id();
   if (!mount_points_->GetRegisteredPath(mount_name, &root_path) &&
       !system_mount_points_->GetRegisteredPath(mount_name, &root_path)) {
-    return FilePath();
+    return base::FilePath();
   }
 
   return root_path.DirName();
@@ -116,7 +116,8 @@ bool CrosMountPointProvider::IsAccessAllowed(
 }
 
 // TODO(zelidrag): Share this code with SandboxMountPointProvider impl.
-bool CrosMountPointProvider::IsRestrictedFileName(const FilePath& path) const {
+bool CrosMountPointProvider::IsRestrictedFileName(
+    const base::FilePath& path) const {
   return false;
 }
 
@@ -147,12 +148,12 @@ void CrosMountPointProvider::GrantFullAccessToExtension(
   for (size_t i = 0; i < files.size(); ++i) {
     file_access_permissions_->GrantAccessPermission(
         extension_id,
-        FilePath::FromUTF8Unsafe(files[i].name));
+        base::FilePath::FromUTF8Unsafe(files[i].name));
   }
 }
 
 void CrosMountPointProvider::GrantFileAccessToExtension(
-    const std::string& extension_id, const FilePath& virtual_path) {
+    const std::string& extension_id, const base::FilePath& virtual_path) {
   // All we care about here is access from extensions for now.
   DCHECK(special_storage_policy_->IsFileHandler(extension_id));
   if (!special_storage_policy_->IsFileHandler(extension_id))
@@ -160,7 +161,7 @@ void CrosMountPointProvider::GrantFileAccessToExtension(
 
   std::string id;
   fileapi::FileSystemType type;
-  FilePath path;
+  base::FilePath path;
   if (!mount_points_->CrackVirtualPath(virtual_path, &id, &type, &path) &&
       !system_mount_points_->CrackVirtualPath(virtual_path,
                                               &id, &type, &path)) {
@@ -180,12 +181,12 @@ void CrosMountPointProvider::RevokeAccessForExtension(
   file_access_permissions_->RevokePermissions(extension_id);
 }
 
-std::vector<FilePath> CrosMountPointProvider::GetRootDirectories() const {
+std::vector<base::FilePath> CrosMountPointProvider::GetRootDirectories() const {
   std::vector<fileapi::MountPoints::MountPointInfo> mount_points;
   mount_points_->AddMountPointInfosTo(&mount_points);
   system_mount_points_->AddMountPointInfosTo(&mount_points);
 
-  std::vector<FilePath> root_dirs;
+  std::vector<base::FilePath> root_dirs;
   for (size_t i = 0; i < mount_points.size(); ++i)
     root_dirs.push_back(mount_points[i].path);
   return root_dirs;
@@ -272,8 +273,8 @@ fileapi::FileStreamWriter* CrosMountPointProvider::CreateFileStreamWriter(
   return new fileapi::LocalFileStreamWriter(url.path(), offset);
 }
 
-bool CrosMountPointProvider::GetVirtualPath(const FilePath& filesystem_path,
-                                           FilePath* virtual_path) {
+bool CrosMountPointProvider::GetVirtualPath(const base::FilePath& filesystem_path,
+                                           base::FilePath* virtual_path) {
   return mount_points_->GetVirtualPath(filesystem_path, virtual_path) ||
          system_mount_points_->GetVirtualPath(filesystem_path, virtual_path);
 }
diff --git a/webkit/chromeos/fileapi/cros_mount_point_provider.h b/webkit/chromeos/fileapi/cros_mount_point_provider.h
index 8da1f54a47723e..9c9723843ecd54 100644
--- a/webkit/chromeos/fileapi/cros_mount_point_provider.h
+++ b/webkit/chromeos/fileapi/cros_mount_point_provider.h
@@ -56,11 +56,11 @@ class WEBKIT_STORAGE_EXPORT CrosMountPointProvider
       fileapi::FileSystemType type,
       bool create,
       const ValidateFileSystemCallback& callback) OVERRIDE;
-  virtual FilePath GetFileSystemRootPathOnFileThread(
+  virtual base::FilePath GetFileSystemRootPathOnFileThread(
       const fileapi::FileSystemURL& url,
       bool create) OVERRIDE;
   virtual bool IsAccessAllowed(const fileapi::FileSystemURL& url) OVERRIDE;
-  virtual bool IsRestrictedFileName(const FilePath& filename) const OVERRIDE;
+  virtual bool IsRestrictedFileName(const base::FilePath& filename) const OVERRIDE;
   virtual fileapi::FileSystemFileUtil* GetFileUtil(
       fileapi::FileSystemType type) OVERRIDE;
   virtual fileapi::AsyncFileUtil* GetAsyncFileUtil(
@@ -89,15 +89,15 @@ class WEBKIT_STORAGE_EXPORT CrosMountPointProvider
       const DeleteFileSystemCallback& callback) OVERRIDE;
 
   // fileapi::ExternalFileSystemMountPointProvider overrides.
-  virtual std::vector<FilePath> GetRootDirectories() const OVERRIDE;
+  virtual std::vector<base::FilePath> GetRootDirectories() const OVERRIDE;
   virtual void GrantFullAccessToExtension(
       const std::string& extension_id) OVERRIDE;
   virtual void GrantFileAccessToExtension(
-      const std::string& extension_id, const FilePath& virtual_path) OVERRIDE;
+      const std::string& extension_id, const base::FilePath& virtual_path) OVERRIDE;
   virtual void RevokeAccessForExtension(
       const std::string& extension_id) OVERRIDE;
-  virtual bool GetVirtualPath(const FilePath& filesystem_path,
-                              FilePath* virtual_path) OVERRIDE;
+  virtual bool GetVirtualPath(const base::FilePath& filesystem_path,
+                              base::FilePath* virtual_path) OVERRIDE;
 
  private:
   fileapi::RemoteFileSystemProxyInterface* GetRemoteProxy(
diff --git a/webkit/chromeos/fileapi/cros_mount_point_provider_unittest.cc b/webkit/chromeos/fileapi/cros_mount_point_provider_unittest.cc
index eb338e34d3be89..df4e3b20fa8dd1 100644
--- a/webkit/chromeos/fileapi/cros_mount_point_provider_unittest.cc
+++ b/webkit/chromeos/fileapi/cros_mount_point_provider_unittest.cc
@@ -27,7 +27,7 @@ FileSystemURL CreateFileSystemURL(const std::string& extension,
   return mount_points->CreateCrackedFileSystemURL(
       GURL("chrome-extension://" + extension + "/"),
       fileapi::kFileSystemTypeExternal,
-      FilePath::FromUTF8Unsafe(path));
+      base::FilePath::FromUTF8Unsafe(path));
 }
 
 TEST(CrosMountPointProviderTest, DefaultMountPoints) {
@@ -39,14 +39,14 @@ TEST(CrosMountPointProviderTest, DefaultMountPoints) {
       storage_policy,
       mount_points.get(),
       fileapi::ExternalMountPoints::GetSystemInstance());
-  std::vector<FilePath> root_dirs = provider.GetRootDirectories();
-  std::set<FilePath> root_dirs_set(root_dirs.begin(), root_dirs.end());
+  std::vector<base::FilePath> root_dirs = provider.GetRootDirectories();
+  std::set<base::FilePath> root_dirs_set(root_dirs.begin(), root_dirs.end());
 
   // By default there should be 3 mount points (in system mount points):
   EXPECT_EQ(3u, root_dirs.size());
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/media/removable"))));
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/media/archive"))));
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/usr/share/oem"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/media/removable"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/media/archive"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/usr/share/oem"))));
 }
 
 TEST(CrosMountPointProviderTest, GetRootDirectories) {
@@ -66,26 +66,26 @@ TEST(CrosMountPointProviderTest, GetRootDirectories) {
   // Register 'local' test mount points.
   mount_points->RegisterFileSystem("c",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(FPL("/a/b/c")));
+                                   base::FilePath(FPL("/a/b/c")));
   mount_points->RegisterFileSystem("d",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(FPL("/b/c/d")));
+                                   base::FilePath(FPL("/b/c/d")));
 
   // Register system test mount points.
   system_mount_points->RegisterFileSystem("d",
                                           fileapi::kFileSystemTypeNativeLocal,
-                                          FilePath(FPL("/g/c/d")));
+                                          base::FilePath(FPL("/g/c/d")));
   system_mount_points->RegisterFileSystem("e",
                                           fileapi::kFileSystemTypeNativeLocal,
-                                          FilePath(FPL("/g/d/e")));
+                                          base::FilePath(FPL("/g/d/e")));
 
-  std::vector<FilePath> root_dirs = provider.GetRootDirectories();
-  std::set<FilePath> root_dirs_set(root_dirs.begin(), root_dirs.end());
+  std::vector<base::FilePath> root_dirs = provider.GetRootDirectories();
+  std::set<base::FilePath> root_dirs_set(root_dirs.begin(), root_dirs.end());
   EXPECT_EQ(4u, root_dirs.size());
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/a/b/c"))));
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/b/c/d"))));
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/g/c/d"))));
-  EXPECT_TRUE(root_dirs_set.count(FilePath(FPL("/g/d/e"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/a/b/c"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/b/c/d"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/g/c/d"))));
+  EXPECT_TRUE(root_dirs_set.count(base::FilePath(FPL("/g/d/e"))));
 }
 
 TEST(CrosMountPointProviderTest, AccessPermissions) {
@@ -110,22 +110,22 @@ TEST(CrosMountPointProviderTest, AccessPermissions) {
   ASSERT_TRUE(system_mount_points->RegisterFileSystem(
       "system",
       fileapi::kFileSystemTypeNativeLocal,
-      FilePath(FPL("/g/system"))));
+      base::FilePath(FPL("/g/system"))));
   ASSERT_TRUE(mount_points->RegisterFileSystem(
       "removable",
       fileapi::kFileSystemTypeNativeLocal,
-      FilePath(FPL("/media/removable"))));
+      base::FilePath(FPL("/media/removable"))));
   ASSERT_TRUE(mount_points->RegisterFileSystem(
       "oem",
       fileapi::kFileSystemTypeRestrictedNativeLocal,
-      FilePath(FPL("/usr/share/oem"))));
+      base::FilePath(FPL("/usr/share/oem"))));
 
   // Provider specific mount point access.
   EXPECT_FALSE(provider.IsAccessAllowed(
       CreateFileSystemURL(extension, "removable/foo", mount_points.get())));
 
   provider.GrantFileAccessToExtension(extension,
-                                      FilePath(FPL("removable/foo")));
+                                      base::FilePath(FPL("removable/foo")));
   EXPECT_TRUE(provider.IsAccessAllowed(
       CreateFileSystemURL(extension, "removable/foo", mount_points.get())));
   EXPECT_FALSE(provider.IsAccessAllowed(
@@ -135,14 +135,14 @@ TEST(CrosMountPointProviderTest, AccessPermissions) {
   EXPECT_FALSE(provider.IsAccessAllowed(
       CreateFileSystemURL(extension, "system/foo", system_mount_points.get())));
 
-  provider.GrantFileAccessToExtension(extension, FilePath(FPL("system/foo")));
+  provider.GrantFileAccessToExtension(extension, base::FilePath(FPL("system/foo")));
   EXPECT_TRUE(provider.IsAccessAllowed(
       CreateFileSystemURL(extension, "system/foo", system_mount_points.get())));
   EXPECT_FALSE(provider.IsAccessAllowed(CreateFileSystemURL(
       extension, "system/foo1", system_mount_points.get())));
 
   // oem is restricted file system.
-  provider.GrantFileAccessToExtension(extension, FilePath(FPL("oem/foo")));
+  provider.GrantFileAccessToExtension(extension, base::FilePath(FPL("oem/foo")));
   // The extension should not be able to access the file even if
   // GrantFileAccessToExtension was called.
   EXPECT_FALSE(provider.IsAccessAllowed(
@@ -165,7 +165,7 @@ TEST(CrosMountPointProviderTest, AccessPermissions) {
   ASSERT_TRUE(mount_points->RegisterFileSystem(
       "test",
       fileapi::kFileSystemTypeNativeLocal,
-      FilePath(FPL("/foo/test"))));
+      base::FilePath(FPL("/foo/test"))));
   EXPECT_FALSE(provider.IsAccessAllowed(
       CreateFileSystemURL(extension, "test_/foo", mount_points.get())));
 
@@ -176,7 +176,7 @@ TEST(CrosMountPointProviderTest, AccessPermissions) {
   fileapi::FileSystemURL internal_url = FileSystemURL::CreateForTest(
       GURL("chrome://foo"),
       fileapi::kFileSystemTypeExternal,
-      FilePath(FPL("removable/")));
+      base::FilePath(FPL("removable/")));
   // Internal WebUI should have full access.
   EXPECT_TRUE(provider.IsAccessAllowed(internal_url));
 }
@@ -196,24 +196,24 @@ TEST(CrosMountPointProvider, GetVirtualPathConflictWithSystemPoints) {
 
   // Provider specific mount points.
   ASSERT_TRUE(
-      mount_points->RegisterFileSystem("b", type, FilePath(FPL("/a/b"))));
+      mount_points->RegisterFileSystem("b", type, base::FilePath(FPL("/a/b"))));
   ASSERT_TRUE(
-      mount_points->RegisterFileSystem("y", type, FilePath(FPL("/z/y"))));
+      mount_points->RegisterFileSystem("y", type, base::FilePath(FPL("/z/y"))));
   ASSERT_TRUE(
-      mount_points->RegisterFileSystem("n", type, FilePath(FPL("/m/n"))));
+      mount_points->RegisterFileSystem("n", type, base::FilePath(FPL("/m/n"))));
 
   // System mount points
   ASSERT_TRUE(system_mount_points->RegisterFileSystem(
-      "gb", type, FilePath(FPL("/a/b"))));
+      "gb", type, base::FilePath(FPL("/a/b"))));
   ASSERT_TRUE(
-      system_mount_points->RegisterFileSystem("gz", type, FilePath(FPL("/z"))));
+      system_mount_points->RegisterFileSystem("gz", type, base::FilePath(FPL("/z"))));
   ASSERT_TRUE(system_mount_points->RegisterFileSystem(
-       "gp", type, FilePath(FPL("/m/n/o/p"))));
+       "gp", type, base::FilePath(FPL("/m/n/o/p"))));
 
   struct TestCase {
-    const FilePath::CharType* const local_path;
+    const base::FilePath::CharType* const local_path;
     bool success;
-    const FilePath::CharType* const virtual_path;
+    const base::FilePath::CharType* const virtual_path;
   };
 
   const TestCase kTestCases[] = {
@@ -231,8 +231,8 @@ TEST(CrosMountPointProvider, GetVirtualPathConflictWithSystemPoints) {
 
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kTestCases); ++i) {
     // Initialize virtual path with a value.
-    FilePath virtual_path(FPL("/mount"));
-    FilePath local_path(kTestCases[i].local_path);
+    base::FilePath virtual_path(FPL("/mount"));
+    base::FilePath local_path(kTestCases[i].local_path);
     EXPECT_EQ(kTestCases[i].success,
               provider.GetVirtualPath(local_path, &virtual_path))
         << "Resolving " << kTestCases[i].local_path;
@@ -242,7 +242,7 @@ TEST(CrosMountPointProvider, GetVirtualPathConflictWithSystemPoints) {
     if (!kTestCases[i].success)
       continue;
 
-    FilePath expected_virtual_path(kTestCases[i].virtual_path);
+    base::FilePath expected_virtual_path(kTestCases[i].virtual_path);
     EXPECT_EQ(expected_virtual_path, virtual_path)
         << "Resolving " << kTestCases[i].local_path;
   }
diff --git a/webkit/chromeos/fileapi/file_access_permissions.cc b/webkit/chromeos/fileapi/file_access_permissions.cc
index 6ab5a049203279..a435a555f6ba42 100644
--- a/webkit/chromeos/fileapi/file_access_permissions.cc
+++ b/webkit/chromeos/fileapi/file_access_permissions.cc
@@ -15,7 +15,7 @@ FileAccessPermissions::~FileAccessPermissions() {}
 
 
 void FileAccessPermissions::GrantAccessPermission(
-    const std::string& extension_id, const FilePath& path) {
+    const std::string& extension_id, const base::FilePath& path) {
   base::AutoLock locker(lock_);
   PathAccessMap::iterator path_map_iter = path_map_.find(extension_id);
   if (path_map_iter == path_map_.end()) {
@@ -30,7 +30,7 @@ void FileAccessPermissions::GrantAccessPermission(
 }
 
 bool FileAccessPermissions::HasAccessPermission(
-    const std::string& extension_id, const FilePath& path) {
+    const std::string& extension_id, const base::FilePath& path) {
   base::AutoLock locker(lock_);
   PathAccessMap::const_iterator path_map_iter = path_map_.find(extension_id);
   if (path_map_iter == path_map_.end())
@@ -38,8 +38,8 @@ bool FileAccessPermissions::HasAccessPermission(
 
   // Check this file and walk up its directory tree to find if this extension
   // has access to it.
-  FilePath current_path = path.StripTrailingSeparators();
-  FilePath last_path;
+  base::FilePath current_path = path.StripTrailingSeparators();
+  base::FilePath last_path;
   while (current_path != last_path) {
     if (path_map_iter->second.find(current_path) != path_map_iter->second.end())
       return true;
diff --git a/webkit/chromeos/fileapi/file_access_permissions.h b/webkit/chromeos/fileapi/file_access_permissions.h
index 9aa0d8ba6a05ac..ba20b444012a42 100644
--- a/webkit/chromeos/fileapi/file_access_permissions.h
+++ b/webkit/chromeos/fileapi/file_access_permissions.h
@@ -21,15 +21,15 @@ class FileAccessPermissions {
 
   // Grants |extension_id| access to |path|.
   void GrantAccessPermission(const std::string& extension_id,
-                             const FilePath& path);
+                             const base::FilePath& path);
   // Checks id |extension_id| has permission to access to |path|.
   bool HasAccessPermission(const std::string& extension_id,
-                           const FilePath& path);
+                           const base::FilePath& path);
   // Revokes all file permissions for |extension_id|.
   void RevokePermissions(const std::string& extension_id);
 
  private:
-  typedef std::set<FilePath> PathSet;
+  typedef std::set<base::FilePath> PathSet;
   typedef std::map<std::string, PathSet> PathAccessMap;
 
   base::Lock lock_;  // Synchronize all access to path_map_.
diff --git a/webkit/chromeos/fileapi/file_access_permissions_unittest.cc b/webkit/chromeos/fileapi/file_access_permissions_unittest.cc
index b3efbfee5e9f96..e6cc9edaa35aaf 100644
--- a/webkit/chromeos/fileapi/file_access_permissions_unittest.cc
+++ b/webkit/chromeos/fileapi/file_access_permissions_unittest.cc
@@ -11,15 +11,15 @@ class FileAccessPermissionsTest : public testing::Test {
 
 TEST_F(FileAccessPermissionsTest, FileAccessChecks) {
 #if defined(OS_WIN)
-  FilePath good_dir(FILE_PATH_LITERAL("c:\\root\\dir"));
-  FilePath bad_dir(FILE_PATH_LITERAL("c:\\root"));
-  FilePath good_file(FILE_PATH_LITERAL("c:\\root\\dir\\good_file.txt"));
-  FilePath bad_file(FILE_PATH_LITERAL("c:\\root\\dir\\bad_file.txt"));
+  base::FilePath good_dir(FILE_PATH_LITERAL("c:\\root\\dir"));
+  base::FilePath bad_dir(FILE_PATH_LITERAL("c:\\root"));
+  base::FilePath good_file(FILE_PATH_LITERAL("c:\\root\\dir\\good_file.txt"));
+  base::FilePath bad_file(FILE_PATH_LITERAL("c:\\root\\dir\\bad_file.txt"));
 #elif defined(OS_POSIX)
-  FilePath good_dir(FILE_PATH_LITERAL("/root/dir"));
-  FilePath bad_dir(FILE_PATH_LITERAL("/root"));
-  FilePath good_file(FILE_PATH_LITERAL("/root/dir/good_file.txt"));
-  FilePath bad_file(FILE_PATH_LITERAL("/root/dir/bad_file.txt"));
+  base::FilePath good_dir(FILE_PATH_LITERAL("/root/dir"));
+  base::FilePath bad_dir(FILE_PATH_LITERAL("/root"));
+  base::FilePath good_file(FILE_PATH_LITERAL("/root/dir/good_file.txt"));
+  base::FilePath bad_file(FILE_PATH_LITERAL("/root/dir/bad_file.txt"));
 #endif
   std::string extension1("ddammdhioacbehjngdmkjcjbnfginlla");
   std::string extension2("jkhdjkhkhsdkfhsdkhrterwmtermeter");
diff --git a/webkit/chromeos/fileapi/file_util_async.h b/webkit/chromeos/fileapi/file_util_async.h
index 3cec09dbd6ac35..6d3cca6dbe709b 100644
--- a/webkit/chromeos/fileapi/file_util_async.h
+++ b/webkit/chromeos/fileapi/file_util_async.h
@@ -51,33 +51,33 @@ class FileUtilAsync {
   // PLATFORM_FILE_OK is passed to |callback| with a pointer to newly
   // created AsyncFileStream object. The caller should delete the
   // stream. On failure, an error code is passed instead.
-  virtual void Open(const FilePath& file_path,
+  virtual void Open(const base::FilePath& file_path,
                     int file_flags,  // PlatformFileFlags
                     const OpenCallback& callback) = 0;
 
   // Gets file info of the given |file_path|. On success,
   // PLATFORM_FILE_OK is passed to |callback| with the the obtained file
   // info. On failure, an error code is passed instead.
-  virtual void GetFileInfo(const FilePath& file_path,
+  virtual void GetFileInfo(const base::FilePath& file_path,
                            const GetFileInfoCallback& callback) = 0;
 
   // Creates a file of the given |file_path|. On success,
   // PLATFORM_FILE_OK is passed to |callback|. On failure, an error code
   // is passed instead.
-  virtual void Create(const FilePath& file_path,
+  virtual void Create(const base::FilePath& file_path,
                       const StatusCallback& callback) = 0;
 
   // Truncates a file of the given |file_path| to |length|. On success,
   // PLATFORM_FILE_OK is passed to |callback|. On failure, an error code
   // is passed instead.
-  virtual void Truncate(const FilePath& file_path,
+  virtual void Truncate(const base::FilePath& file_path,
                         int64 length,
                         const StatusCallback& callback) = 0;
 
   // Modifies the timestamps of a file of the given |file_path|. On
   // success, PLATFORM_FILE_OK is passed to |callback|. On failure, an
   // error code is passed instead.
-  virtual void Touch(const FilePath& file_path,
+  virtual void Touch(const base::FilePath& file_path,
                      const base::Time& last_access_time,
                      const base::Time& last_modified_time,
                      const StatusCallback& callback) = 0;
@@ -86,14 +86,14 @@ class FileUtilAsync {
   // is true, removes the contents of the given directory recursively. On
   // success, PLATFORM_FILE_OK is passed to |callback|. On failure, an
   // error code is passed instead.
-  virtual void Remove(const FilePath& file_path,
+  virtual void Remove(const base::FilePath& file_path,
                       bool recursive,
                       const StatusCallback& callback) = 0;
 
   // Creates a directory of the given |dir_path|. On success,
   // PLATFORM_FILE_OK is passed to |callback|. On failure, an error code
   // is passed instead.
-  virtual void CreateDirectory(const FilePath& dir_path,
+  virtual void CreateDirectory(const base::FilePath& dir_path,
                                const StatusCallback& callback) = 0;
 
   // Reads a directory of the given |dir_path|. On success,
@@ -112,7 +112,7 @@ class FileUtilAsync {
   // before callback is actually called.
   //
   // TODO(olege): Maybe make it possible to read only a part of the directory.
-  virtual void ReadDirectory(const FilePath& dir_path,
+  virtual void ReadDirectory(const base::FilePath& dir_path,
                              const ReadDirectoryCallback& callback) = 0;
 
   // TODO(olege): Add LocalCopy and LocalMove.
diff --git a/webkit/chromeos/fileapi/memory_file_util.cc b/webkit/chromeos/fileapi/memory_file_util.cc
index dcedf5a2982695..6d79687c3d5145 100644
--- a/webkit/chromeos/fileapi/memory_file_util.cc
+++ b/webkit/chromeos/fileapi/memory_file_util.cc
@@ -134,7 +134,7 @@ MemoryFileUtil::FileEntry::FileEntry()
 MemoryFileUtil::FileEntry::~FileEntry() {
 }
 
-MemoryFileUtil::MemoryFileUtil(const FilePath& root_path)
+MemoryFileUtil::MemoryFileUtil(const base::FilePath& root_path)
     : read_directory_buffer_size_(kDefaultReadDirectoryBufferSize) {
   FileEntry root;
   root.is_directory = true;
@@ -179,7 +179,7 @@ MemoryFileUtil::~MemoryFileUtil() {
 // - OpenVerifiedFile
 //
 void MemoryFileUtil::Open(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int flags,
     const OpenCallback& callback) {
   int create_flag = flags & (base::PLATFORM_FILE_OPEN |
@@ -230,7 +230,7 @@ void MemoryFileUtil::Open(
 }
 
 void MemoryFileUtil::GetFileInfo(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const GetFileInfoCallback& callback) {
   MessageLoop::current()->PostTask(
       FROM_HERE,
@@ -239,7 +239,7 @@ void MemoryFileUtil::GetFileInfo(
 }
 
 void MemoryFileUtil::Create(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const StatusCallback& callback) {
   MessageLoop::current()->PostTask(
       FROM_HERE,
@@ -248,7 +248,7 @@ void MemoryFileUtil::Create(
 }
 
 void MemoryFileUtil::Truncate(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int64 length,
     const StatusCallback& callback) {
   MessageLoop::current()->PostTask(
@@ -258,7 +258,7 @@ void MemoryFileUtil::Truncate(
 }
 
 void MemoryFileUtil::Touch(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const base::Time& last_access_time,
     const base::Time& last_modified_time,
     const StatusCallback& callback) {
@@ -270,7 +270,7 @@ void MemoryFileUtil::Touch(
 }
 
 void MemoryFileUtil::Remove(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     bool recursive,
     const StatusCallback& callback) {
   if (recursive) {
@@ -289,7 +289,7 @@ void MemoryFileUtil::Remove(
 }
 
 void MemoryFileUtil::CreateDirectory(
-    const FilePath& dir_path,
+    const base::FilePath& dir_path,
     const StatusCallback& callback) {
   MessageLoop::current()->PostTask(
       FROM_HERE,
@@ -299,16 +299,16 @@ void MemoryFileUtil::CreateDirectory(
 }
 
 void MemoryFileUtil::ReadDirectory(
-    const FilePath& dir_path,
+    const base::FilePath& dir_path,
     const ReadDirectoryCallback& callback) {
   MessageLoop::current()->PostTask(
       FROM_HERE,
       base::Bind(&MemoryFileUtil::DoReadDirectory,
                  base::Unretained(this), dir_path.StripTrailingSeparators(),
-                 FilePath(), callback));
+                 base::FilePath(), callback));
 }
 
-void MemoryFileUtil::DoGetFileInfo(const FilePath& file_path,
+void MemoryFileUtil::DoGetFileInfo(const base::FilePath& file_path,
                                    const GetFileInfoCallback& callback) {
   base::PlatformFileInfo file_info;
 
@@ -334,7 +334,7 @@ void MemoryFileUtil::DoGetFileInfo(const FilePath& file_path,
 }
 
 void MemoryFileUtil::DoCreate(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     bool is_directory,
     const StatusCallback& callback) {
   if (FileExists(file_path)) {
@@ -356,7 +356,7 @@ void MemoryFileUtil::DoCreate(
 }
 
 void MemoryFileUtil::DoTruncate(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int64 length,
     const StatusCallback& callback) {
   FileIterator file_it = files_.find(file_path);
@@ -374,7 +374,7 @@ void MemoryFileUtil::DoTruncate(
 }
 
 void MemoryFileUtil::DoTouch(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const base::Time& last_modified_time,
     const StatusCallback& callback) {
   FileIterator file_it = files_.find(file_path);
@@ -390,7 +390,7 @@ void MemoryFileUtil::DoTouch(
 }
 
 void MemoryFileUtil::DoRemoveSingleFile(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const StatusCallback& callback) {
   FileIterator file_it = files_.find(file_path);
   if (file_it == files_.end()) {
@@ -416,7 +416,7 @@ void MemoryFileUtil::DoRemoveSingleFile(
 }
 
 void MemoryFileUtil::DoRemoveRecursive(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const StatusCallback& callback) {
   FileIterator file_it = files_.find(file_path);
   if (file_it == files_.end()) {
@@ -445,10 +445,10 @@ void MemoryFileUtil::DoRemoveRecursive(
 }
 
 void MemoryFileUtil::DoReadDirectory(
-    const FilePath& dir_path,
-    const FilePath& in_from,
+    const base::FilePath& dir_path,
+    const base::FilePath& in_from,
     const ReadDirectoryCallback& callback) {
-  FilePath from = in_from;
+  base::FilePath from = in_from;
   read_directory_buffer_.clear();
 
   if (!FileExists(dir_path)) {
@@ -510,7 +510,7 @@ void MemoryFileUtil::DoReadDirectory(
 }
 
 void MemoryFileUtil::OpenVerifiedFile(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int flags,
     const OpenCallback& callback) {
   FileIterator file_it = files_.find(file_path);
@@ -523,7 +523,7 @@ void MemoryFileUtil::OpenVerifiedFile(
 }
 
 void MemoryFileUtil::DidGetFileInfoForOpen(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int flags,
     const OpenCallback& callback,
     PlatformFileError get_info_result,
@@ -550,7 +550,7 @@ void MemoryFileUtil::DidGetFileInfoForOpen(
 }
 
 void MemoryFileUtil::OpenTruncatedFileOrCreate(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int flags,
     const OpenCallback& callback,
     PlatformFileError result) {
@@ -571,7 +571,7 @@ void MemoryFileUtil::OpenTruncatedFileOrCreate(
 }
 
 void MemoryFileUtil::DidCreateOrTruncateForOpen(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     int flags,
     int64 size,
     const OpenCallback& callback,
diff --git a/webkit/chromeos/fileapi/memory_file_util.h b/webkit/chromeos/fileapi/memory_file_util.h
index 723bada7c5780f..adbdce6b8cc490 100644
--- a/webkit/chromeos/fileapi/memory_file_util.h
+++ b/webkit/chromeos/fileapi/memory_file_util.h
@@ -28,104 +28,104 @@ class MemoryFileUtil : public FileUtilAsync {
     base::Time last_modified;
   };
 
-  MemoryFileUtil(const FilePath& root_path);
+  MemoryFileUtil(const base::FilePath& root_path);
   virtual ~MemoryFileUtil();
 
   // FileUtilAsync overrides.
-  virtual void Open(const FilePath& file_path,
+  virtual void Open(const base::FilePath& file_path,
                     int file_flags,  // PlatformFileFlags
                     const OpenCallback& callback) OVERRIDE;
-  virtual void GetFileInfo(const FilePath& file_path,
+  virtual void GetFileInfo(const base::FilePath& file_path,
                            const GetFileInfoCallback& callback) OVERRIDE;
-  virtual void Create(const FilePath& file_path,
+  virtual void Create(const base::FilePath& file_path,
                       const StatusCallback& callback) OVERRIDE;
-  virtual void Truncate(const FilePath& file_path,
+  virtual void Truncate(const base::FilePath& file_path,
                         int64 length,
                         const StatusCallback& callback) OVERRIDE;
   // This FS ignores last_access_time.
-  virtual void Touch(const FilePath& file_path,
+  virtual void Touch(const base::FilePath& file_path,
                      const base::Time& last_access_time,
                      const base::Time& last_modified_time,
                      const StatusCallback& callback) OVERRIDE;
-  virtual void Remove(const FilePath& file_path,
+  virtual void Remove(const base::FilePath& file_path,
                       bool recursive,
                       const StatusCallback& callback) OVERRIDE;
-  virtual void CreateDirectory(const FilePath& dir_path,
+  virtual void CreateDirectory(const base::FilePath& dir_path,
                                const StatusCallback& callback) OVERRIDE;
-  virtual void ReadDirectory(const FilePath& dir_path,
+  virtual void ReadDirectory(const base::FilePath& dir_path,
                              const ReadDirectoryCallback& callback) OVERRIDE;
 
  private:
   friend class MemoryFileUtilTest;
 
-  typedef std::map<FilePath, FileEntry>::iterator FileIterator;
-  typedef std::map<FilePath, FileEntry>::const_iterator ConstFileIterator;
+  typedef std::map<base::FilePath, FileEntry>::iterator FileIterator;
+  typedef std::map<base::FilePath, FileEntry>::const_iterator ConstFileIterator;
 
   // Returns true if the given |file_path| is present in the file system.
-  bool FileExists(const FilePath& file_path) const {
+  bool FileExists(const base::FilePath& file_path) const {
     return files_.find(file_path) != files_.end();
   }
 
   // Returns true if the given |file_path| is present and a directory.
-  bool IsDirectory(const FilePath& file_path) const {
+  bool IsDirectory(const base::FilePath& file_path) const {
     ConstFileIterator it = files_.find(file_path);
     return it != files_.end() && it->second.is_directory;
   }
 
   // Callback function used to implement GetFileInfo().
-  void DoGetFileInfo(const FilePath& file_path,
+  void DoGetFileInfo(const base::FilePath& file_path,
                      const GetFileInfoCallback& callback);
 
   // Callback function used to implement Create().
-  void DoCreate(const FilePath& file_path,
+  void DoCreate(const base::FilePath& file_path,
                 bool is_directory,
                 const StatusCallback& callback);
 
   // Callback function used to implement Truncate().
-  void DoTruncate(const FilePath& file_path,
+  void DoTruncate(const base::FilePath& file_path,
                   int64 length,
                   const StatusCallback& callback);
 
   // Callback function used to implement Touch().
-  void DoTouch(const FilePath& file_path,
+  void DoTouch(const base::FilePath& file_path,
                const base::Time& last_modified_time,
                const StatusCallback& callback);
 
   // Callback function used to implement Remove().
-  void DoRemoveSingleFile(const FilePath& file_path,
+  void DoRemoveSingleFile(const base::FilePath& file_path,
                           const StatusCallback& callback);
 
   // Callback function used to implement Remove().
-  void DoRemoveRecursive(const FilePath& file_path,
+  void DoRemoveRecursive(const base::FilePath& file_path,
                          const StatusCallback& callback);
 
   // Will start enumerating with file path |from|. If |from| path is
   // empty, will start from the beginning.
-  void DoReadDirectory(const FilePath& dir_path,
-                       const FilePath& from,
+  void DoReadDirectory(const base::FilePath& dir_path,
+                       const base::FilePath& from,
                        const ReadDirectoryCallback& callback);
 
   // Opens a file of the given |file_path| with |flags|. A file is
   // guaranteed to be present at |file_path|.
-  void OpenVerifiedFile(const FilePath& file_path,
+  void OpenVerifiedFile(const base::FilePath& file_path,
                         int flags,
                         const OpenCallback& callback);
 
   // Callback function used to implement Open().
-  void DidGetFileInfoForOpen(const FilePath& file_path,
+  void DidGetFileInfoForOpen(const base::FilePath& file_path,
                              int flags,
                              const OpenCallback& callback,
                              PlatformFileError get_info_result,
                              const base::PlatformFileInfo& file_info);
 
   // Callback function used to implement Open().
-  void OpenTruncatedFileOrCreate(const FilePath& file_path,
+  void OpenTruncatedFileOrCreate(const base::FilePath& file_path,
                                  int flags,
                                  const OpenCallback& callback,
                                  PlatformFileError result);
 
   // Callback function used to implement Open().
-  void DidCreateOrTruncateForOpen(const FilePath& file_path,
+  void DidCreateOrTruncateForOpen(const base::FilePath& file_path,
                                   int flags,
                                   int64 size,
                                   const OpenCallback& callback,
@@ -138,7 +138,7 @@ class MemoryFileUtil : public FileUtilAsync {
   }
 
   // The files in the file system.
-  std::map<FilePath, FileEntry> files_;
+  std::map<base::FilePath, FileEntry> files_;
   size_t read_directory_buffer_size_;
   std::vector<DirectoryEntry> read_directory_buffer_;
 
diff --git a/webkit/chromeos/fileapi/memory_file_util_unittest.cc b/webkit/chromeos/fileapi/memory_file_util_unittest.cc
index 024e849878a722..b2a0c099ed120d 100644
--- a/webkit/chromeos/fileapi/memory_file_util_unittest.cc
+++ b/webkit/chromeos/fileapi/memory_file_util_unittest.cc
@@ -10,7 +10,7 @@
 #include "webkit/chromeos/fileapi/memory_file_util.h"
 
 namespace {
-const FilePath::CharType kRootPath[] = "/mnt/memory";
+const base::FilePath::CharType kRootPath[] = "/mnt/memory";
 const char kTestString[] = "A test string. A test string.";
 const char kTestStringLength = arraysize(kTestString) - 1;
 }  // namespace
@@ -33,7 +33,7 @@ class MemoryFileUtilTest : public testing::Test {
   }
 
   void SetUp() {
-    file_util_.reset(new MemoryFileUtil(FilePath(kRootPath)));
+    file_util_.reset(new MemoryFileUtil(base::FilePath(kRootPath)));
   }
 
   MemoryFileUtil* file_util() {
@@ -105,13 +105,13 @@ class MemoryFileUtilTest : public testing::Test {
                       request_id);
   }
 
-  int CreateEmptyFile(const FilePath& file_path) {
+  int CreateEmptyFile(const base::FilePath& file_path) {
     int request_id = GetNextRequestId();
     file_util_->Create(file_path, GetStatusCallback(request_id));
     return request_id;
   }
 
-  int CreateNonEmptyFile(const FilePath& file_path,
+  int CreateNonEmptyFile(const base::FilePath& file_path,
                          const char* data,
                          int length) {
     int request_id = GetNextRequestId();
@@ -234,7 +234,7 @@ class MemoryFileUtilTest : public testing::Test {
 
 TEST_F(MemoryFileUtilTest, TestCreateGetFileInfo) {
   const int request_id1 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test.txt"),
                            GetGetFileInfoCallback(request_id1));
 
   // In case the file system is truely asynchronous, RunAllPending is not
@@ -250,7 +250,7 @@ TEST_F(MemoryFileUtilTest, TestCreateGetFileInfo) {
   base::Time start_create = base::Time::Now();
 
   const int request_id2 = GetNextRequestId();
-  file_util()->Create(FilePath("/mnt/memory/test.txt"),
+  file_util()->Create(base::FilePath("/mnt/memory/test.txt"),
                       GetStatusCallback(request_id2));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(CALLBACK_TYPE_STATUS, GetStatusType(request_id2));
@@ -258,7 +258,7 @@ TEST_F(MemoryFileUtilTest, TestCreateGetFileInfo) {
   ASSERT_EQ(base::PLATFORM_FILE_OK, status.result);
 
   const int request_id3 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test.txt"),
                            GetGetFileInfoCallback(request_id3));
   MessageLoop::current()->RunUntilIdle();
 
@@ -280,7 +280,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check that the file does not exist.
 
   const int request_id1 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id1));
 
   MessageLoop::current()->RunUntilIdle();
@@ -293,7 +293,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
 
   base::Time start_create = base::Time::Now();
   const int request_id2 = GetNextRequestId();
-  file_util()->Open(FilePath("/mnt/memory/test1.txt"),
+  file_util()->Open(base::FilePath("/mnt/memory/test1.txt"),
                     base::PLATFORM_FILE_CREATE_ALWAYS |
                     base::PLATFORM_FILE_WRITE,
                     GetOpenCallback(request_id2));
@@ -310,7 +310,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check that file was created and has 0 size.
 
   const int request_id3 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id3));
   MessageLoop::current()->RunUntilIdle();
 
@@ -340,7 +340,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check that the file has now size 10 and correct modification time.
 
   const int request_id5 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id5));
   MessageLoop::current()->RunUntilIdle();
 
@@ -369,7 +369,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check the file size & modification time.
 
   const int request_id7 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id7));
   MessageLoop::current()->RunUntilIdle();
 
@@ -383,7 +383,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Open file for reading.
 
   const int request_id8 = GetNextRequestId();
-  file_util()->Open(FilePath("/mnt/memory/test1.txt"),
+  file_util()->Open(base::FilePath("/mnt/memory/test1.txt"),
                     base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
                     GetOpenCallback(request_id8));
   MessageLoop::current()->RunUntilIdle();
@@ -413,7 +413,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check that size & modification time have not changed.
 
   const int request_id10 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id10));
   MessageLoop::current()->RunUntilIdle();
 
@@ -427,7 +427,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Open once more for writing.
 
   const int request_id11 = GetNextRequestId();
-  file_util()->Open(FilePath("/mnt/memory/test1.txt"),
+  file_util()->Open(base::FilePath("/mnt/memory/test1.txt"),
                     base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_WRITE,
                     GetOpenCallback(request_id11));
   MessageLoop::current()->RunUntilIdle();
@@ -441,7 +441,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check that the size has not changed.
 
   const int request_id12 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id12));
   MessageLoop::current()->RunUntilIdle();
 
@@ -489,7 +489,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
   // Check size.
 
   const int request_id17 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/test1.txt"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/test1.txt"),
                            GetGetFileInfoCallback(request_id17));
   MessageLoop::current()->RunUntilIdle();
   status = GetStatus(request_id17);
@@ -531,7 +531,7 @@ TEST_F(MemoryFileUtilTest, TestReadWrite) {
 TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Check the directory is empty.
   const int request_id0 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/"),
                              GetReadDirectoryCallback(request_id0));
 
   MessageLoop::current()->RunUntilIdle();
@@ -548,18 +548,18 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // complete before starting the next one.
 
   base::Time start_create = base::Time::Now();
-  CreateEmptyFile(FilePath("/mnt/memory/a"));
+  CreateEmptyFile(base::FilePath("/mnt/memory/a"));
 
   int request_id1 = GetNextRequestId();
-  file_util()->CreateDirectory(FilePath("/mnt/memory/b"),
+  file_util()->CreateDirectory(base::FilePath("/mnt/memory/b"),
                                GetStatusCallback(request_id1));
 
-  CreateNonEmptyFile(FilePath("/mnt/memory/longer_file_name.txt"),
+  CreateNonEmptyFile(base::FilePath("/mnt/memory/longer_file_name.txt"),
                      kTestString,
                      kTestStringLength);
 
   int request_id2 = GetNextRequestId();
-  file_util()->CreateDirectory(FilePath("/mnt/memory/c"),
+  file_util()->CreateDirectory(base::FilePath("/mnt/memory/c"),
                                GetStatusCallback(request_id2));
 
   MessageLoop::current()->RunUntilIdle();
@@ -574,16 +574,16 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   set_read_directory_buffer_size(5);  // Should complete in one go.
 
   request_id1 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory"),
                              GetReadDirectoryCallback(request_id1));
   request_id2 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/a"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/a"),
                              GetReadDirectoryCallback(request_id2));
   const int request_id3 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/b/"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/b/"),
                              GetReadDirectoryCallback(request_id3));
   const int request_id4 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/d/"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/d/"),
                              GetReadDirectoryCallback(request_id4));
 
   MessageLoop::current()->RunUntilIdle();
@@ -595,7 +595,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   ASSERT_EQ(1, status.called);  // Because the number of entries < 5.
   ASSERT_EQ(4u, status.entries.size());
 
-  std::set<FilePath::StringType> seen;
+  std::set<base::FilePath::StringType> seen;
 
   for (FileUtilAsync::FileList::const_iterator it = status.entries.begin();
        it != status.entries.end();
@@ -644,26 +644,26 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // /mnt/memory/b/g/h       0
 
   start_create = base::Time::Now();
-  CreateNonEmptyFile(FilePath("/mnt/memory/b/c"),
+  CreateNonEmptyFile(base::FilePath("/mnt/memory/b/c"),
                      kTestString,
                      kTestStringLength);
   request_id1 = GetNextRequestId();
-  file_util()->CreateDirectory(FilePath("/mnt/memory/b/d"),
+  file_util()->CreateDirectory(base::FilePath("/mnt/memory/b/d"),
                                GetStatusCallback(request_id1));
-  CreateEmptyFile(FilePath("/mnt/memory/b/e"));
-  CreateNonEmptyFile(FilePath("/mnt/memory/b/f"),
+  CreateEmptyFile(base::FilePath("/mnt/memory/b/e"));
+  CreateNonEmptyFile(base::FilePath("/mnt/memory/b/f"),
                      kTestString,
                      kTestStringLength);
   request_id2 = GetNextRequestId();
-  file_util()->CreateDirectory(FilePath("/mnt/memory/b/g"),
+  file_util()->CreateDirectory(base::FilePath("/mnt/memory/b/g"),
                                GetStatusCallback(request_id1));
-  CreateNonEmptyFile(FilePath("/mnt/memory/b/i"),
+  CreateNonEmptyFile(base::FilePath("/mnt/memory/b/i"),
                      kTestString,
                      kTestStringLength);
 
   MessageLoop::current()->RunUntilIdle();
 
-  CreateEmptyFile(FilePath("/mnt/memory/b/g/h"));
+  CreateEmptyFile(base::FilePath("/mnt/memory/b/g/h"));
 
   MessageLoop::current()->RunUntilIdle();
   end_create = base::Time::Now();
@@ -671,7 +671,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Read /mnt/memory and check that the number of entries is unchanged.
 
   request_id1 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory"),
                              GetReadDirectoryCallback(request_id1));
 
   MessageLoop::current()->RunUntilIdle();
@@ -686,7 +686,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Read /mnt/memory/b
 
   request_id1 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/b"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/b"),
                              GetReadDirectoryCallback(request_id1));
 
   MessageLoop::current()->RunUntilIdle();
@@ -741,7 +741,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Remove single file: /mnt/memory/b/f
 
   request_id1 = GetNextRequestId();
-  file_util()->Remove(FilePath("/mnt/memory/b/f"), false /* recursive */,
+  file_util()->Remove(base::FilePath("/mnt/memory/b/f"), false /* recursive */,
                       GetStatusCallback(request_id1));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
@@ -749,7 +749,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Check the number of files in b/
 
   request_id1 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/b"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/b"),
                              GetReadDirectoryCallback(request_id1));
 
   MessageLoop::current()->RunUntilIdle();
@@ -763,7 +763,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Try remove /mnt/memory/b non-recursively (error)
 
   request_id1 = GetNextRequestId();
-  file_util()->Remove(FilePath("/mnt/memory/b"), false /* recursive */,
+  file_util()->Remove(base::FilePath("/mnt/memory/b"), false /* recursive */,
                       GetStatusCallback(request_id1));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_A_FILE,
@@ -772,13 +772,13 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Non-recursively remove empty directory.
 
   request_id1 = GetNextRequestId();
-  file_util()->Remove(FilePath("/mnt/memory/b/d"), false /* recursive */,
+  file_util()->Remove(base::FilePath("/mnt/memory/b/d"), false /* recursive */,
                       GetStatusCallback(request_id1));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
 
   request_id1 = GetNextRequestId();
-  file_util()->GetFileInfo(FilePath("/mnt/memory/b/d"),
+  file_util()->GetFileInfo(base::FilePath("/mnt/memory/b/d"),
                            GetGetFileInfoCallback(request_id1));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, GetStatus(request_id1).result);
@@ -786,7 +786,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // Remove /mnt/memory/b recursively.
 
   request_id1 = GetNextRequestId();
-  file_util()->Remove(FilePath("/mnt/memory/b"), true /* recursive */,
+  file_util()->Remove(base::FilePath("/mnt/memory/b"), true /* recursive */,
                       GetStatusCallback(request_id1));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(base::PLATFORM_FILE_OK, GetStatus(request_id1).result);
@@ -794,7 +794,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // ReadDirectory /mnt/memory/b -> not found
 
   request_id1 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory/b"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory/b"),
                              GetReadDirectoryCallback(request_id1));
   MessageLoop::current()->RunUntilIdle();
   ASSERT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, GetStatus(request_id1).result);
@@ -802,7 +802,7 @@ TEST_F(MemoryFileUtilTest, TestDirectoryOperations) {
   // ReadDirectory /mnt/memory
 
   request_id1 = GetNextRequestId();
-  file_util()->ReadDirectory(FilePath("/mnt/memory"),
+  file_util()->ReadDirectory(base::FilePath("/mnt/memory"),
                              GetReadDirectoryCallback(request_id1));
 
   MessageLoop::current()->RunUntilIdle();
diff --git a/webkit/chromeos/fileapi/remote_file_stream_writer.cc b/webkit/chromeos/fileapi/remote_file_stream_writer.cc
index 6fcbd65377fb11..d51df11abb23ff 100644
--- a/webkit/chromeos/fileapi/remote_file_stream_writer.cc
+++ b/webkit/chromeos/fileapi/remote_file_stream_writer.cc
@@ -56,7 +56,7 @@ void RemoteFileStreamWriter::OnFileOpened(
     int buf_len,
     const net::CompletionCallback& callback,
     base::PlatformFileError open_result,
-    const FilePath& local_path,
+    const base::FilePath& local_path,
     const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref) {
   has_pending_create_snapshot_ = false;
   if (!pending_cancel_callback_.is_null()) {
diff --git a/webkit/chromeos/fileapi/remote_file_stream_writer.h b/webkit/chromeos/fileapi/remote_file_stream_writer.h
index cf341bd3347806..c68e9db7ff5ac2 100644
--- a/webkit/chromeos/fileapi/remote_file_stream_writer.h
+++ b/webkit/chromeos/fileapi/remote_file_stream_writer.h
@@ -52,7 +52,7 @@ class RemoteFileStreamWriter : public fileapi::FileStreamWriter {
       int buf_len,
       const net::CompletionCallback& callback,
       base::PlatformFileError open_result,
-      const FilePath& local_path,
+      const base::FilePath& local_path,
       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
   // Calls |pending_cancel_callback_|, assuming it is non-null.
   void InvokePendingCancelCallback(int result);
diff --git a/webkit/chromeos/fileapi/remote_file_system_operation.cc b/webkit/chromeos/fileapi/remote_file_system_operation.cc
index 218b5b74727739..5f0843ec8997e7 100644
--- a/webkit/chromeos/fileapi/remote_file_system_operation.cc
+++ b/webkit/chromeos/fileapi/remote_file_system_operation.cc
@@ -236,7 +236,7 @@ void RemoteFileSystemOperation::DidDirectoryExists(
     const StatusCallback& callback,
     base::PlatformFileError rv,
     const base::PlatformFileInfo& file_info,
-    const FilePath& unused) {
+    const base::FilePath& unused) {
   if (rv == base::PLATFORM_FILE_OK && !file_info.is_directory)
     rv = base::PLATFORM_FILE_ERROR_NOT_A_DIRECTORY;
   callback.Run(rv);
@@ -246,7 +246,7 @@ void RemoteFileSystemOperation::DidFileExists(
     const StatusCallback& callback,
     base::PlatformFileError rv,
     const base::PlatformFileInfo& file_info,
-    const FilePath& unused) {
+    const base::FilePath& unused) {
   if (rv == base::PLATFORM_FILE_OK && file_info.is_directory)
     rv = base::PLATFORM_FILE_ERROR_NOT_A_FILE;
   callback.Run(rv);
@@ -256,7 +256,7 @@ void RemoteFileSystemOperation::DidGetMetadata(
     const GetMetadataCallback& callback,
     base::PlatformFileError rv,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   callback.Run(rv, file_info, platform_path);
 }
 
@@ -310,7 +310,7 @@ void RemoteFileSystemOperation::DidCreateSnapshotFile(
     const SnapshotFileCallback& callback,
     base::PlatformFileError result,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path,
+    const base::FilePath& platform_path,
     const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref) {
   callback.Run(result, file_info, platform_path, file_ref);
 }
diff --git a/webkit/chromeos/fileapi/remote_file_system_operation.h b/webkit/chromeos/fileapi/remote_file_system_operation.h
index 84a6f7dc8add7f..ba429c1a0d8ecf 100644
--- a/webkit/chromeos/fileapi/remote_file_system_operation.h
+++ b/webkit/chromeos/fileapi/remote_file_system_operation.h
@@ -88,15 +88,15 @@ class RemoteFileSystemOperation : public fileapi::FileSystemOperation {
   void DidDirectoryExists(const StatusCallback& callback,
                           base::PlatformFileError rv,
                           const base::PlatformFileInfo& file_info,
-                          const FilePath& unused);
+                          const base::FilePath& unused);
   void DidFileExists(const StatusCallback& callback,
                      base::PlatformFileError rv,
                      const base::PlatformFileInfo& file_info,
-                     const FilePath& unused);
+                     const base::FilePath& unused);
   void DidGetMetadata(const GetMetadataCallback& callback,
                       base::PlatformFileError rv,
                       const base::PlatformFileInfo& file_info,
-                      const FilePath& platform_path);
+                      const base::FilePath& platform_path);
   void DidReadDirectory(
       const ReadDirectoryCallback& callback,
       base::PlatformFileError rv,
@@ -111,7 +111,7 @@ class RemoteFileSystemOperation : public fileapi::FileSystemOperation {
       const SnapshotFileCallback& callback,
       base::PlatformFileError result,
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
   void DidOpenFile(
       const OpenFileCallback& callback,
diff --git a/webkit/database/database_tracker.cc b/webkit/database/database_tracker.cc
index 824c8a2fe57f50..2cdcfe87e24920 100644
--- a/webkit/database/database_tracker.cc
+++ b/webkit/database/database_tracker.cc
@@ -27,18 +27,18 @@
 
 namespace webkit_database {
 
-const FilePath::CharType kDatabaseDirectoryName[] =
+const base::FilePath::CharType kDatabaseDirectoryName[] =
     FILE_PATH_LITERAL("databases");
-const FilePath::CharType kIncognitoDatabaseDirectoryName[] =
+const base::FilePath::CharType kIncognitoDatabaseDirectoryName[] =
     FILE_PATH_LITERAL("databases-incognito");
-const FilePath::CharType kTrackerDatabaseFileName[] =
+const base::FilePath::CharType kTrackerDatabaseFileName[] =
     FILE_PATH_LITERAL("Databases.db");
 static const int kCurrentVersion = 2;
 static const int kCompatibleVersion = 1;
 
-const FilePath::CharType kTemporaryDirectoryPrefix[] =
+const base::FilePath::CharType kTemporaryDirectoryPrefix[] =
     FILE_PATH_LITERAL("DeleteMe");
-const FilePath::CharType kTemporaryDirectoryPattern[] =
+const base::FilePath::CharType kTemporaryDirectoryPattern[] =
     FILE_PATH_LITERAL("DeleteMe*");
 
 OriginInfo::OriginInfo()
@@ -77,7 +77,7 @@ OriginInfo::OriginInfo(const string16& origin, int64 total_size)
     : origin_(origin), total_size_(total_size) {}
 
 DatabaseTracker::DatabaseTracker(
-    const FilePath& profile_path,
+    const base::FilePath& profile_path,
     bool is_incognito,
     quota::SpecialStoragePolicy* special_storage_policy,
     quota::QuotaManagerProxy* quota_manager_proxy,
@@ -280,21 +280,21 @@ string16 DatabaseTracker::GetOriginDirectory(
   return origin_directory;
 }
 
-FilePath DatabaseTracker::GetFullDBFilePath(
+base::FilePath DatabaseTracker::GetFullDBFilePath(
     const string16& origin_identifier,
     const string16& database_name) {
   DCHECK(!origin_identifier.empty());
   if (!LazyInit())
-    return FilePath();
+    return base::FilePath();
 
   int64 id = databases_table_->GetDatabaseID(
       origin_identifier, database_name);
   if (id < 0)
-    return FilePath();
+    return base::FilePath();
 
-  FilePath file_name = FilePath::FromWStringHack(
+  base::FilePath file_name = base::FilePath::FromWStringHack(
       UTF8ToWide(base::Int64ToString(id)));
-  return db_dir_.Append(FilePath::FromWStringHack(
+  return db_dir_.Append(base::FilePath::FromWStringHack(
       UTF16ToWide(GetOriginDirectory(origin_identifier)))).Append(file_name);
 }
 
@@ -352,7 +352,7 @@ bool DatabaseTracker::DeleteClosedDatabase(const string16& origin_identifier,
       GetDBFileSize(origin_identifier, database_name) : 0;
 
   // Try to delete the file on the hard drive.
-  FilePath db_file = GetFullDBFilePath(origin_identifier, database_name);
+  base::FilePath db_file = GetFullDBFilePath(origin_identifier, database_name);
   if (file_util::PathExists(db_file) && !file_util::Delete(db_file, false))
     return false;
 
@@ -398,13 +398,13 @@ bool DatabaseTracker::DeleteOrigin(const string16& origin_identifier,
   }
 
   origins_info_map_.erase(origin_identifier);
-  FilePath origin_dir = db_dir_.Append(FilePath::FromWStringHack(
+  base::FilePath origin_dir = db_dir_.Append(base::FilePath::FromWStringHack(
       UTF16ToWide(origin_identifier)));
 
   // Create a temporary directory to move possibly still existing databases to,
   // as we can't delete the origin directory on windows if it contains opened
   // files.
-  FilePath new_origin_dir;
+  base::FilePath new_origin_dir;
   file_util::CreateTemporaryDirInDir(db_dir_,
                                      kTemporaryDirectoryPrefix,
                                      &new_origin_dir);
@@ -412,9 +412,9 @@ bool DatabaseTracker::DeleteOrigin(const string16& origin_identifier,
       origin_dir,
       false,
       file_util::FileEnumerator::FILES);
-  for (FilePath database = databases.Next(); !database.empty();
+  for (base::FilePath database = databases.Next(); !database.empty();
        database = databases.Next()) {
-    FilePath new_file = new_origin_dir.Append(database.BaseName());
+    base::FilePath new_file = new_origin_dir.Append(database.BaseName());
     file_util::Move(database, new_file);
   }
   file_util::Delete(origin_dir, true);
@@ -458,7 +458,7 @@ bool DatabaseTracker::LazyInit() {
           false,
           file_util::FileEnumerator::DIRECTORIES,
           kTemporaryDirectoryPattern);
-      for (FilePath directory = directories.Next(); !directory.empty();
+      for (base::FilePath directory = directories.Next(); !directory.empty();
            directory = directories.Next()) {
         file_util::Delete(directory, true);
       }
@@ -466,8 +466,8 @@ bool DatabaseTracker::LazyInit() {
 
     // If the tracker database exists, but it's corrupt or doesn't
     // have a meta table, delete the database directory.
-    const FilePath kTrackerDatabaseFullPath =
-        db_dir_.Append(FilePath(kTrackerDatabaseFileName));
+    const base::FilePath kTrackerDatabaseFullPath =
+        db_dir_.Append(base::FilePath(kTrackerDatabaseFileName));
     if (file_util::DirectoryExists(db_dir_) &&
         file_util::PathExists(kTrackerDatabaseFullPath) &&
         (!db_->Open(kTrackerDatabaseFullPath) ||
@@ -574,7 +574,8 @@ DatabaseTracker::CachedOriginInfo* DatabaseTracker::MaybeGetCachedOriginInfo(
 
 int64 DatabaseTracker::GetDBFileSize(const string16& origin_identifier,
                                      const string16& database_name) {
-  FilePath db_file_name = GetFullDBFilePath(origin_identifier, database_name);
+  base::FilePath db_file_name = GetFullDBFilePath(origin_identifier,
+                                                  database_name);
   int64 db_file_size = 0;
   if (!file_util::GetFileSize(db_file_name, &db_file_size))
     db_file_size = 0;
@@ -690,7 +691,7 @@ int DatabaseTracker::DeleteDataModifiedSince(
       rv = net::ERR_FAILED;
     for (std::vector<DatabaseDetails>::const_iterator db = details.begin();
          db != details.end(); ++db) {
-      FilePath db_file = GetFullDBFilePath(*ori, db->database_name);
+      base::FilePath db_file = GetFullDBFilePath(*ori, db->database_name);
       base::PlatformFileInfo file_info;
       file_util::GetFileInfo(db_file, &file_info);
       if (file_info.last_modified < cutoff)
@@ -789,7 +790,7 @@ void DatabaseTracker::DeleteIncognitoDBDirectory() {
        it != incognito_file_handles_.end(); it++)
     base::ClosePlatformFile(it->second);
 
-  FilePath incognito_db_dir =
+  base::FilePath incognito_db_dir =
       profile_path_.Append(kIncognitoDatabaseDirectoryName);
   if (file_util::DirectoryExists(incognito_db_dir))
     file_util::Delete(incognito_db_dir, true);
diff --git a/webkit/database/database_tracker.h b/webkit/database/database_tracker.h
index df3079a140f217..956a72e6b67888 100644
--- a/webkit/database/database_tracker.h
+++ b/webkit/database/database_tracker.h
@@ -38,8 +38,9 @@ class SpecialStoragePolicy;
 
 namespace webkit_database {
 
-WEBKIT_STORAGE_EXPORT extern const FilePath::CharType kDatabaseDirectoryName[];
-WEBKIT_STORAGE_EXPORT extern const FilePath::CharType
+WEBKIT_STORAGE_EXPORT extern const base::FilePath::CharType
+    kDatabaseDirectoryName[];
+WEBKIT_STORAGE_EXPORT extern const base::FilePath::CharType
     kTrackerDatabaseFileName[];
 
 class DatabasesTable;
@@ -93,7 +94,7 @@ class WEBKIT_STORAGE_EXPORT DatabaseTracker
     virtual ~Observer() {}
   };
 
-  DatabaseTracker(const FilePath& profile_path,
+  DatabaseTracker(const base::FilePath& profile_path,
                   bool is_incognito,
                   quota::SpecialStoragePolicy* special_storage_policy,
                   quota::QuotaManagerProxy* quota_manager_proxy,
@@ -119,8 +120,8 @@ class WEBKIT_STORAGE_EXPORT DatabaseTracker
 
   void CloseTrackerDatabaseAndClearCaches();
 
-  const FilePath& DatabaseDirectory() const { return db_dir_; }
-  FilePath GetFullDBFilePath(const string16& origin_identifier,
+  const base::FilePath& DatabaseDirectory() const { return db_dir_; }
+  base::FilePath GetFullDBFilePath(const string16& origin_identifier,
                              const string16& database_name);
 
   // virtual for unit-testing only
@@ -264,8 +265,8 @@ class WEBKIT_STORAGE_EXPORT DatabaseTracker
   const bool is_incognito_;
   bool force_keep_session_state_;
   bool shutting_down_;
-  const FilePath profile_path_;
-  const FilePath db_dir_;
+  const base::FilePath profile_path_;
+  const base::FilePath db_dir_;
   scoped_ptr<sql::Connection> db_;
   scoped_ptr<DatabasesTable> databases_table_;
   scoped_ptr<sql::MetaTable> meta_table_;
diff --git a/webkit/database/database_tracker_unittest.cc b/webkit/database/database_tracker_unittest.cc
index ef95d8f2aa6f0e..e3e373827207a7 100644
--- a/webkit/database/database_tracker_unittest.cc
+++ b/webkit/database/database_tracker_unittest.cc
@@ -158,7 +158,7 @@ class TestQuotaManagerProxy : public quota::QuotaManagerProxy {
 };
 
 
-bool EnsureFileOfSize(const FilePath& file_path, int64 length) {
+bool EnsureFileOfSize(const base::FilePath& file_path, int64 length) {
   base::PlatformFileError error_code(base::PLATFORM_FILE_ERROR_FAILED);
   base::PlatformFile file =
       base::CreatePlatformFile(
@@ -215,10 +215,10 @@ class DatabaseTracker_TestHelper_Test {
                             &database_size);
 
     EXPECT_TRUE(file_util::CreateDirectory(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(
+        base::FilePath::FromWStringHack(UTF16ToWide(
             tracker->GetOriginDirectory(kOrigin1))))));
     EXPECT_TRUE(file_util::CreateDirectory(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(
+        base::FilePath::FromWStringHack(UTF16ToWide(
             tracker->GetOriginDirectory(kOrigin2))))));
     EXPECT_EQ(1, file_util::WriteFile(
         tracker->GetFullDBFilePath(kOrigin1, kDB1), "a", 1));
@@ -244,13 +244,13 @@ class DatabaseTracker_TestHelper_Test {
     result = callback.GetResult(result);
     EXPECT_EQ(net::OK, result);
     EXPECT_FALSE(file_util::PathExists(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(kOrigin1)))));
+        base::FilePath::FromWStringHack(UTF16ToWide(kOrigin1)))));
 
     // Recreate db1.
     tracker->DatabaseOpened(kOrigin1, kDB1, kDescription, 0,
                             &database_size);
     EXPECT_TRUE(file_util::CreateDirectory(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(
+        base::FilePath::FromWStringHack(UTF16ToWide(
             tracker->GetOriginDirectory(kOrigin1))))));
     EXPECT_EQ(1, file_util::WriteFile(
         tracker->GetFullDBFilePath(kOrigin1, kDB1), "a", 1));
@@ -280,7 +280,7 @@ class DatabaseTracker_TestHelper_Test {
     result = callback.GetResult(result);
     EXPECT_EQ(net::OK, result);
     EXPECT_FALSE(file_util::PathExists(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(kOrigin1)))));
+        base::FilePath::FromWStringHack(UTF16ToWide(kOrigin1)))));
     EXPECT_TRUE(
         file_util::PathExists(tracker->GetFullDBFilePath(kOrigin2, kDB2)));
     EXPECT_TRUE(
@@ -340,10 +340,10 @@ class DatabaseTracker_TestHelper_Test {
     // Write some data to each file and check that the listeners are
     // called with the appropriate values.
     EXPECT_TRUE(file_util::CreateDirectory(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(
+        base::FilePath::FromWStringHack(UTF16ToWide(
             tracker->GetOriginDirectory(kOrigin1))))));
     EXPECT_TRUE(file_util::CreateDirectory(tracker->DatabaseDirectory().Append(
-        FilePath::FromWStringHack(UTF16ToWide(
+        base::FilePath::FromWStringHack(UTF16ToWide(
             tracker->GetOriginDirectory(kOrigin2))))));
     EXPECT_EQ(1, file_util::WriteFile(
         tracker->GetFullDBFilePath(kOrigin1, kDB1), "a", 1));
@@ -461,7 +461,7 @@ class DatabaseTracker_TestHelper_Test {
     EXPECT_TRUE(test_quota_proxy->WasAccessNotified(kOrigin));
     test_quota_proxy->reset();
 
-    FilePath db_file(tracker->GetFullDBFilePath(kOriginId, kName));
+    base::FilePath db_file(tracker->GetFullDBFilePath(kOriginId, kName));
     EXPECT_TRUE(file_util::CreateDirectory(db_file.DirName()));
     EXPECT_TRUE(EnsureFileOfSize(db_file, 10));
     tracker->DatabaseModified(kOriginId, kName);
@@ -543,8 +543,8 @@ class DatabaseTracker_TestHelper_Test {
     MessageLoop message_loop;
     base::ScopedTempDir temp_dir;
     ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-    FilePath origin1_db_dir;
-    FilePath origin2_db_dir;
+    base::FilePath origin1_db_dir;
+    base::FilePath origin2_db_dir;
     {
       scoped_refptr<quota::MockSpecialStoragePolicy> special_storage_policy =
           new quota::MockSpecialStoragePolicy;
@@ -563,7 +563,7 @@ class DatabaseTracker_TestHelper_Test {
       EXPECT_EQ(0, database_size);
 
       // Write some data to each file.
-      FilePath db_file;
+      base::FilePath db_file;
       db_file = tracker->GetFullDBFilePath(kOrigin1, kDB1);
       EXPECT_TRUE(file_util::CreateDirectory(db_file.DirName()));
       EXPECT_TRUE(EnsureFileOfSize(db_file, 1));
@@ -599,7 +599,7 @@ class DatabaseTracker_TestHelper_Test {
     EXPECT_EQ(kOrigin1, origins_info[0].GetOrigin());
     EXPECT_TRUE(
         file_util::PathExists(tracker->GetFullDBFilePath(kOrigin1, kDB1)));
-    EXPECT_EQ(FilePath(), tracker->GetFullDBFilePath(kOrigin2, kDB2));
+    EXPECT_EQ(base::FilePath(), tracker->GetFullDBFilePath(kOrigin2, kDB2));
 
     // The origin directory of kOrigin1 remains, but the origin directory of
     // kOrigin2 is deleted.
@@ -621,8 +621,8 @@ class DatabaseTracker_TestHelper_Test {
     MessageLoop message_loop;
     base::ScopedTempDir temp_dir;
     ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-    FilePath origin1_db_dir;
-    FilePath origin2_db_dir;
+    base::FilePath origin1_db_dir;
+    base::FilePath origin2_db_dir;
     {
       scoped_refptr<quota::MockSpecialStoragePolicy> special_storage_policy =
           new quota::MockSpecialStoragePolicy;
@@ -642,7 +642,7 @@ class DatabaseTracker_TestHelper_Test {
       EXPECT_EQ(0, database_size);
 
       // Write some data to each file.
-      FilePath db_file;
+      base::FilePath db_file;
       db_file = tracker->GetFullDBFilePath(kOrigin1, kDB1);
       EXPECT_TRUE(file_util::CreateDirectory(db_file.DirName()));
       EXPECT_TRUE(EnsureFileOfSize(db_file, 1));
@@ -759,7 +759,7 @@ class DatabaseTracker_TestHelper_Test {
     int64 database_size = 0;
     tracker->DatabaseOpened(kOriginId, kName, kDescription, 0,
                             &database_size);
-    FilePath spoof_db_file = tracker->GetFullDBFilePath(kOriginId, kName);
+    base::FilePath spoof_db_file = tracker->GetFullDBFilePath(kOriginId, kName);
     EXPECT_FALSE(tracker->GetFullDBFilePath(kOriginId, kName).empty());
     EXPECT_TRUE(file_util::CreateDirectory(spoof_db_file.DirName()));
     EXPECT_TRUE(EnsureFileOfSize(spoof_db_file, 1));
@@ -787,7 +787,7 @@ class DatabaseTracker_TestHelper_Test {
     // a spoof_db_file on disk in the expected location.
     tracker->DatabaseOpened(kOriginId, kName, kDescription, 0,
                             &database_size);
-    FilePath spoof_db_file2 = tracker->GetFullDBFilePath(kOriginId, kName);
+    base::FilePath spoof_db_file2 = tracker->GetFullDBFilePath(kOriginId, kName);
     EXPECT_FALSE(tracker->GetFullDBFilePath(kOriginId, kName).empty());
     EXPECT_NE(spoof_db_file, spoof_db_file2);
     EXPECT_TRUE(file_util::CreateDirectory(spoof_db_file2.DirName()));
diff --git a/webkit/database/database_util.cc b/webkit/database/database_util.cc
index be56a4be863a64..6d5ff95bd81132 100644
--- a/webkit/database/database_util.cc
+++ b/webkit/database/database_util.cc
@@ -45,17 +45,17 @@ bool DatabaseUtil::CrackVfsFileName(const string16& vfs_file_name,
   return true;
 }
 
-FilePath DatabaseUtil::GetFullFilePathForVfsFile(
+base::FilePath DatabaseUtil::GetFullFilePathForVfsFile(
     DatabaseTracker* db_tracker, const string16& vfs_file_name) {
   string16 origin_identifier;
   string16 database_name;
   string16 sqlite_suffix;
   if (!CrackVfsFileName(vfs_file_name, &origin_identifier,
                         &database_name, &sqlite_suffix)) {
-    return FilePath(); // invalid vfs_file_name
+    return base::FilePath(); // invalid vfs_file_name
   }
 
-  FilePath full_path = db_tracker->GetFullDBFilePath(
+  base::FilePath full_path = db_tracker->GetFullDBFilePath(
       origin_identifier, database_name);
   if (!full_path.empty() && !sqlite_suffix.empty()) {
     DCHECK(full_path.Extension().empty());
@@ -64,8 +64,8 @@ FilePath DatabaseUtil::GetFullFilePathForVfsFile(
   }
   // Watch out for directory traversal attempts from a compromised renderer.
   if (full_path.value().find(FILE_PATH_LITERAL("..")) !=
-          FilePath::StringType::npos)
-    return FilePath();
+          base::FilePath::StringType::npos)
+    return base::FilePath();
   return full_path;
 }
 
diff --git a/webkit/database/database_util.h b/webkit/database/database_util.h
index 67296b37bebdf2..8158f3929a8278 100644
--- a/webkit/database/database_util.h
+++ b/webkit/database/database_util.h
@@ -9,7 +9,9 @@
 #include "googleurl/src/gurl.h"
 #include "webkit/storage/webkit_storage_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace webkit_database {
 
@@ -25,8 +27,8 @@ class WEBKIT_STORAGE_EXPORT DatabaseUtil {
                                string16* origin_identifier,
                                string16* database_name,
                                string16* sqlite_suffix);
-  static FilePath GetFullFilePathForVfsFile(DatabaseTracker* db_tracker,
-                                            const string16& vfs_file_name);
+  static base::FilePath GetFullFilePathForVfsFile(DatabaseTracker* db_tracker,
+                                                  const string16& vfs_file_name);
   static string16 GetOriginIdentifier(const GURL& url);
   static GURL GetOriginFromIdentifier(const string16& origin_identifier);
 };
diff --git a/webkit/database/vfs_backend.cc b/webkit/database/vfs_backend.cc
index a73035d7cb4d1b..8d046e2b5a89a1 100644
--- a/webkit/database/vfs_backend.cc
+++ b/webkit/database/vfs_backend.cc
@@ -55,7 +55,7 @@ bool VfsBackend::OpenFileFlagsAreConsistent(int desired_flags) {
 }
 
 // static
-void VfsBackend::OpenFile(const FilePath& file_path,
+void VfsBackend::OpenFile(const base::FilePath& file_path,
                           int desired_flags,
                           base::PlatformFile* file_handle) {
   DCHECK(!file_path.empty());
@@ -100,7 +100,7 @@ void VfsBackend::OpenFile(const FilePath& file_path,
 
 // static
 void VfsBackend::OpenTempFileInDirectory(
-    const FilePath& dir_path,
+    const base::FilePath& dir_path,
     int desired_flags,
     base::PlatformFile* file_handle) {
   // We should be able to delete temp files when they're closed
@@ -111,7 +111,7 @@ void VfsBackend::OpenTempFileInDirectory(
   }
 
   // Get a unique temp file name in the database directory.
-  FilePath temp_file_path;
+  base::FilePath temp_file_path;
   if (!file_util::CreateTemporaryFileInDir(dir_path, &temp_file_path))
     return;
 
@@ -119,7 +119,7 @@ void VfsBackend::OpenTempFileInDirectory(
 }
 
 // static
-int VfsBackend::DeleteFile(const FilePath& file_path, bool sync_dir) {
+int VfsBackend::DeleteFile(const base::FilePath& file_path, bool sync_dir) {
   if (!file_util::PathExists(file_path))
     return SQLITE_OK;
   if (!file_util::Delete(file_path, false))
@@ -143,7 +143,7 @@ int VfsBackend::DeleteFile(const FilePath& file_path, bool sync_dir) {
 }
 
 // static
-uint32 VfsBackend::GetFileAttributes(const FilePath& file_path) {
+uint32 VfsBackend::GetFileAttributes(const base::FilePath& file_path) {
 #if defined(OS_WIN)
   uint32 attributes = ::GetFileAttributes(file_path.value().c_str());
 #elif defined(OS_POSIX)
@@ -159,7 +159,7 @@ uint32 VfsBackend::GetFileAttributes(const FilePath& file_path) {
 }
 
 // static
-int64 VfsBackend::GetFileSize(const FilePath& file_path) {
+int64 VfsBackend::GetFileSize(const base::FilePath& file_path) {
   int64 size = 0;
   return (file_util::GetFileSize(file_path, &size) ? size : 0);
 }
diff --git a/webkit/database/vfs_backend.h b/webkit/database/vfs_backend.h
index 8fba3fa51b4299..0459958c77859d 100644
--- a/webkit/database/vfs_backend.h
+++ b/webkit/database/vfs_backend.h
@@ -10,25 +10,27 @@
 #include "base/string16.h"
 #include "webkit/storage/webkit_storage_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace webkit_database {
 
 class WEBKIT_STORAGE_EXPORT VfsBackend {
  public:
-  static void OpenFile(const FilePath& file_path,
+  static void OpenFile(const base::FilePath& file_path,
                        int desired_flags,
                        base::PlatformFile* file_handle);
 
-  static void OpenTempFileInDirectory(const FilePath& dir_path,
+  static void OpenTempFileInDirectory(const base::FilePath& dir_path,
                                       int desired_flags,
                                       base::PlatformFile* file_handle);
 
-  static int DeleteFile(const FilePath& file_path, bool sync_dir);
+  static int DeleteFile(const base::FilePath& file_path, bool sync_dir);
 
-  static uint32 GetFileAttributes(const FilePath& file_path);
+  static uint32 GetFileAttributes(const base::FilePath& file_path);
 
-  static int64 GetFileSize(const FilePath& file_path);
+  static int64 GetFileSize(const base::FilePath& file_path);
 
   // Used to make decisions in the DatabaseDispatcherHost.
   static bool OpenTypeIsReadWrite(int desired_flags);
diff --git a/webkit/dom_storage/dom_storage_area.cc b/webkit/dom_storage/dom_storage_area.cc
index a0c83083328a31..d707a3ae74ad47 100644
--- a/webkit/dom_storage/dom_storage_area.cc
+++ b/webkit/dom_storage/dom_storage_area.cc
@@ -33,28 +33,28 @@ DomStorageArea::CommitBatch::~CommitBatch() {}
 
 
 // static
-const FilePath::CharType DomStorageArea::kDatabaseFileExtension[] =
+const base::FilePath::CharType DomStorageArea::kDatabaseFileExtension[] =
     FILE_PATH_LITERAL(".localstorage");
 
 // static
-FilePath DomStorageArea::DatabaseFileNameFromOrigin(const GURL& origin) {
+base::FilePath DomStorageArea::DatabaseFileNameFromOrigin(const GURL& origin) {
   std::string filename = fileapi::GetOriginIdentifierFromURL(origin);
-  // There is no FilePath.AppendExtension() method, so start with just the
+  // There is no base::FilePath.AppendExtension() method, so start with just the
   // extension as the filename, and then InsertBeforeExtension the desired
   // name.
-  return FilePath().Append(kDatabaseFileExtension).
+  return base::FilePath().Append(kDatabaseFileExtension).
       InsertBeforeExtensionASCII(filename);
 }
 
 // static
-GURL DomStorageArea::OriginFromDatabaseFileName(const FilePath& name) {
+GURL DomStorageArea::OriginFromDatabaseFileName(const base::FilePath& name) {
   DCHECK(name.MatchesExtension(kDatabaseFileExtension));
   WebKit::WebString origin_id = webkit_base::FilePathToWebString(
       name.BaseName().RemoveExtension());
   return DatabaseUtil::GetOriginFromIdentifier(origin_id);
 }
 
-DomStorageArea::DomStorageArea(const GURL& origin, const FilePath& directory,
+DomStorageArea::DomStorageArea(const GURL& origin, const base::FilePath& directory,
                                DomStorageTaskRunner* task_runner)
     : namespace_id_(kLocalStorageNamespaceId), origin_(origin),
       directory_(directory),
@@ -64,7 +64,7 @@ DomStorageArea::DomStorageArea(const GURL& origin, const FilePath& directory,
       is_shutdown_(false),
       commit_batches_in_flight_(0) {
   if (!directory.empty()) {
-    FilePath path = directory.Append(DatabaseFileNameFromOrigin(origin_));
+    base::FilePath path = directory.Append(DatabaseFileNameFromOrigin(origin_));
     backing_.reset(new LocalStorageDatabaseAdapter(path));
     is_initial_import_done_ = false;
   }
diff --git a/webkit/dom_storage/dom_storage_area.h b/webkit/dom_storage/dom_storage_area.h
index 9a08acfc5f5e70..d9fbcaeec279f1 100644
--- a/webkit/dom_storage/dom_storage_area.h
+++ b/webkit/dom_storage/dom_storage_area.h
@@ -29,13 +29,13 @@ class WEBKIT_STORAGE_EXPORT DomStorageArea
     : public base::RefCountedThreadSafe<DomStorageArea> {
 
  public:
-  static const FilePath::CharType kDatabaseFileExtension[];
-  static FilePath DatabaseFileNameFromOrigin(const GURL& origin);
-  static GURL OriginFromDatabaseFileName(const FilePath& file_name);
+  static const base::FilePath::CharType kDatabaseFileExtension[];
+  static base::FilePath DatabaseFileNameFromOrigin(const GURL& origin);
+  static GURL OriginFromDatabaseFileName(const base::FilePath& file_name);
 
   // Local storage. Backed on disk if directory is nonempty.
   DomStorageArea(const GURL& origin,
-                 const FilePath& directory,
+                 const base::FilePath& directory,
                  DomStorageTaskRunner* task_runner);
 
   // Session storage. Backed on disk if |session_storage_backing| is not NULL.
@@ -119,7 +119,7 @@ class WEBKIT_STORAGE_EXPORT DomStorageArea
   int64 namespace_id_;
   std::string persistent_namespace_id_;
   GURL origin_;
-  FilePath directory_;
+  base::FilePath directory_;
   scoped_refptr<DomStorageTaskRunner> task_runner_;
   scoped_refptr<DomStorageMap> map_;
   scoped_ptr<DomStorageDatabaseAdapter> backing_;
diff --git a/webkit/dom_storage/dom_storage_area_unittest.cc b/webkit/dom_storage/dom_storage_area_unittest.cc
index 4513ea309eeb91..6667312f786cf0 100644
--- a/webkit/dom_storage/dom_storage_area_unittest.cc
+++ b/webkit/dom_storage/dom_storage_area_unittest.cc
@@ -126,13 +126,13 @@ TEST_F(DomStorageAreaTest, BackingDatabaseOpened) {
   const int64 kSessionStorageNamespaceId = kLocalStorageNamespaceId + 1;
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  const FilePath kExpectedOriginFilePath = temp_dir.path().Append(
+  const base::FilePath kExpectedOriginFilePath = temp_dir.path().Append(
       DomStorageArea::DatabaseFileNameFromOrigin(kOrigin));
 
   // No directory, backing should be null.
   {
     scoped_refptr<DomStorageArea> area(
-        new DomStorageArea(kOrigin, FilePath(), NULL));
+        new DomStorageArea(kOrigin, base::FilePath(), NULL));
     EXPECT_EQ(NULL, area->backing_.get());
     EXPECT_TRUE(area->is_initial_import_done_);
     EXPECT_FALSE(file_util::PathExists(kExpectedOriginFilePath));
@@ -315,9 +315,9 @@ TEST_F(DomStorageAreaTest, DeleteOrigin) {
           new MockDomStorageTaskRunner(base::MessageLoopProxy::current())));
 
   // This test puts files on disk.
-  FilePath db_file_path = static_cast<LocalStorageDatabaseAdapter*>(
+  base::FilePath db_file_path = static_cast<LocalStorageDatabaseAdapter*>(
       area->backing_.get())->db_->file_path();
-  FilePath db_journal_file_path =
+  base::FilePath db_journal_file_path =
       DomStorageDatabase::GetJournalFilePath(db_file_path);
 
   // Nothing bad should happen when invoked w/o any files on disk.
@@ -443,9 +443,9 @@ TEST_F(DomStorageAreaTest, DatabaseFileNames) {
 
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kCases); ++i) {
     GURL origin = GURL(kCases[i].origin).GetOrigin();
-    FilePath file_name = FilePath().AppendASCII(kCases[i].file_name);
-    FilePath journal_file_name =
-        FilePath().AppendASCII(kCases[i].journal_file_name);
+    base::FilePath file_name = base::FilePath().AppendASCII(kCases[i].file_name);
+    base::FilePath journal_file_name =
+        base::FilePath().AppendASCII(kCases[i].journal_file_name);
 
     EXPECT_EQ(file_name,
               DomStorageArea::DatabaseFileNameFromOrigin(origin));
@@ -456,17 +456,17 @@ TEST_F(DomStorageAreaTest, DatabaseFileNames) {
   }
 
   // Also test some DomStorageDatabase::GetJournalFilePath cases here.
-  FilePath parent = FilePath().AppendASCII("a").AppendASCII("b");
+  base::FilePath parent = base::FilePath().AppendASCII("a").AppendASCII("b");
   EXPECT_EQ(
       parent.AppendASCII("file-journal"),
       DomStorageDatabase::GetJournalFilePath(parent.AppendASCII("file")));
   EXPECT_EQ(
-      FilePath().AppendASCII("-journal"),
-      DomStorageDatabase::GetJournalFilePath(FilePath()));
+      base::FilePath().AppendASCII("-journal"),
+      DomStorageDatabase::GetJournalFilePath(base::FilePath()));
   EXPECT_EQ(
-      FilePath().AppendASCII(".extensiononly-journal"),
+      base::FilePath().AppendASCII(".extensiononly-journal"),
       DomStorageDatabase::GetJournalFilePath(
-          FilePath().AppendASCII(".extensiononly")));
+          base::FilePath().AppendASCII(".extensiononly")));
 }
 
 }  // namespace dom_storage
diff --git a/webkit/dom_storage/dom_storage_context.cc b/webkit/dom_storage/dom_storage_context.cc
index 3d32243c221f60..45aae747639668 100644
--- a/webkit/dom_storage/dom_storage_context.cc
+++ b/webkit/dom_storage/dom_storage_context.cc
@@ -25,8 +25,8 @@ namespace dom_storage {
 static const int kSessionStoraceScavengingSeconds = 60;
 
 DomStorageContext::DomStorageContext(
-    const FilePath& localstorage_directory,
-    const FilePath& sessionstorage_directory,
+    const base::FilePath& localstorage_directory,
+    const base::FilePath& sessionstorage_directory,
     quota::SpecialStoragePolicy* special_storage_policy,
     DomStorageTaskRunner* task_runner)
     : localstorage_directory_(localstorage_directory),
@@ -69,7 +69,7 @@ DomStorageNamespace* DomStorageContext::GetStorageNamespace(
         if (!file_util::CreateDirectory(localstorage_directory_)) {
           LOG(ERROR) << "Failed to create 'Local Storage' directory,"
                         " falling back to in-memory only.";
-          localstorage_directory_ = FilePath();
+          localstorage_directory_ = base::FilePath();
         }
       }
       DomStorageNamespace* local =
@@ -89,7 +89,7 @@ void DomStorageContext::GetLocalStorageUsage(
     return;
   FileEnumerator enumerator(localstorage_directory_, false,
                             FileEnumerator::FILES);
-  for (FilePath path = enumerator.Next(); !path.empty();
+  for (base::FilePath path = enumerator.Next(); !path.empty();
        path = enumerator.Next()) {
     if (path.MatchesExtension(DomStorageArea::kDatabaseFileExtension)) {
       LocalStorageUsageInfo info;
@@ -313,7 +313,7 @@ void DomStorageContext::ClearSessionOnlyOrigins() {
         continue;
 
       const bool kNotRecursive = false;
-      FilePath database_file_path = localstorage_directory_.Append(
+      base::FilePath database_file_path = localstorage_directory_.Append(
           DomStorageArea::DatabaseFileNameFromOrigin(origin));
       file_util::Delete(database_file_path, kNotRecursive);
       file_util::Delete(
diff --git a/webkit/dom_storage/dom_storage_context.h b/webkit/dom_storage/dom_storage_context.h
index 3b48833f988ed6..76a92b02647073 100644
--- a/webkit/dom_storage/dom_storage_context.h
+++ b/webkit/dom_storage/dom_storage_context.h
@@ -19,10 +19,10 @@
 #include "googleurl/src/gurl.h"
 #include "webkit/storage/webkit_storage_export.h"
 
-class FilePath;
 class NullableString16;
 
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -86,18 +86,18 @@ class WEBKIT_STORAGE_EXPORT DomStorageContext
   };
 
   DomStorageContext(
-      const FilePath& localstorage_directory,  // empty for incognito profiles
-      const FilePath& sessionstorage_directory,  // empty for incognito profiles
+      const base::FilePath& localstorage_directory,  // empty for incognito profiles
+      const base::FilePath& sessionstorage_directory,  // empty for incognito profiles
       quota::SpecialStoragePolicy* special_storage_policy,
       DomStorageTaskRunner* task_runner);
 
   // Returns the directory path for localStorage, or an empty directory, if
   // there is no backing on disk.
-  const FilePath& localstorage_directory() { return localstorage_directory_; }
+  const base::FilePath& localstorage_directory() { return localstorage_directory_; }
 
   // Returns the directory path for sessionStorage, or an empty directory, if
   // there is no backing on disk.
-  const FilePath& sessionstorage_directory() {
+  const base::FilePath& sessionstorage_directory() {
     return sessionstorage_directory_;
   }
 
@@ -190,12 +190,12 @@ class WEBKIT_STORAGE_EXPORT DomStorageContext
   StorageNamespaceMap namespaces_;
 
   // Where localstorage data is stored, maybe empty for the incognito use case.
-  FilePath localstorage_directory_;
+  base::FilePath localstorage_directory_;
 
   // Where sessionstorage data is stored, maybe empty for the incognito use
   // case. Always empty until the file-backed session storage feature is
   // implemented.
-  FilePath sessionstorage_directory_;
+  base::FilePath sessionstorage_directory_;
 
   // Used to schedule sequenced background tasks.
   scoped_refptr<DomStorageTaskRunner> task_runner_;
diff --git a/webkit/dom_storage/dom_storage_context_unittest.cc b/webkit/dom_storage/dom_storage_context_unittest.cc
index 39e82529a5c88b..f2bebc15c95734 100644
--- a/webkit/dom_storage/dom_storage_context_unittest.cc
+++ b/webkit/dom_storage/dom_storage_context_unittest.cc
@@ -42,7 +42,7 @@ class DomStorageContextTest : public testing::Test {
     task_runner_ = new MockDomStorageTaskRunner(
             base::MessageLoopProxy::current());
     context_ = new DomStorageContext(temp_dir_.path(),
-                                     FilePath(),
+                                     base::FilePath(),
                                      storage_policy_,
                                      task_runner_);
   }
@@ -54,7 +54,7 @@ class DomStorageContextTest : public testing::Test {
   void VerifySingleOriginRemains(const GURL& origin) {
     // Use a new instance to examine the contexts of temp_dir_.
     scoped_refptr<DomStorageContext> context =
-        new DomStorageContext(temp_dir_.path(), FilePath(), NULL, NULL);
+        new DomStorageContext(temp_dir_.path(), base::FilePath(), NULL, NULL);
     std::vector<LocalStorageUsageInfo> infos;
     context->GetLocalStorageUsage(&infos, kDontIncludeFileInfo);
     ASSERT_EQ(1u, infos.size());
@@ -75,7 +75,7 @@ TEST_F(DomStorageContextTest, Basics) {
   // initializes members properly and that invoking methods
   // on a newly created object w/o any data on disk do no harm.
   EXPECT_EQ(temp_dir_.path(), context_->localstorage_directory());
-  EXPECT_EQ(FilePath(), context_->sessionstorage_directory());
+  EXPECT_EQ(base::FilePath(), context_->sessionstorage_directory());
   EXPECT_EQ(storage_policy_.get(), context_->special_storage_policy_.get());
   context_->PurgeMemory();
   context_->DeleteLocalStorage(GURL("http://chromium.org/"));
@@ -108,7 +108,7 @@ TEST_F(DomStorageContextTest, UsageInfo) {
 
   // Create a new context that points to the same directory, see that
   // it knows about the origin that we stored data for.
-  context_ = new DomStorageContext(temp_dir_.path(), FilePath(), NULL, NULL);
+  context_ = new DomStorageContext(temp_dir_.path(), base::FilePath(), NULL, NULL);
   context_->GetLocalStorageUsage(&infos, kDontIncludeFileInfo);
   EXPECT_EQ(1u, infos.size());
   EXPECT_EQ(kOrigin, infos[0].origin);
diff --git a/webkit/dom_storage/dom_storage_database.cc b/webkit/dom_storage/dom_storage_database.cc
index 97fd3da47d8f0d..a49e93bc420398 100644
--- a/webkit/dom_storage/dom_storage_database.cc
+++ b/webkit/dom_storage/dom_storage_database.cc
@@ -13,7 +13,7 @@
 
 namespace {
 
-const FilePath::CharType kJournal[] = FILE_PATH_LITERAL("-journal");
+const base::FilePath::CharType kJournal[] = FILE_PATH_LITERAL("-journal");
 
 class HistogramUniquifier {
  public:
@@ -29,14 +29,14 @@ sql::ErrorDelegate* GetErrorHandlerForDomStorageDatabase() {
 namespace dom_storage {
 
 // static
-FilePath DomStorageDatabase::GetJournalFilePath(
-    const FilePath& database_path) {
-  FilePath::StringType journal_file_name =
+base::FilePath DomStorageDatabase::GetJournalFilePath(
+    const base::FilePath& database_path) {
+  base::FilePath::StringType journal_file_name =
       database_path.BaseName().value() + kJournal;
   return database_path.DirName().Append(journal_file_name);
 }
 
-DomStorageDatabase::DomStorageDatabase(const FilePath& file_path)
+DomStorageDatabase::DomStorageDatabase(const base::FilePath& file_path)
     : file_path_(file_path) {
   // Note: in normal use we should never get an empty backing path here.
   // However, the unit test for this class can contruct an instance
diff --git a/webkit/dom_storage/dom_storage_database.h b/webkit/dom_storage/dom_storage_database.h
index e6fd0db624a4f4..e11a507c62ded8 100644
--- a/webkit/dom_storage/dom_storage_database.h
+++ b/webkit/dom_storage/dom_storage_database.h
@@ -22,9 +22,9 @@ namespace dom_storage {
 // class is designed to be used on a single thread.
 class WEBKIT_STORAGE_EXPORT DomStorageDatabase {
  public:
-  static FilePath GetJournalFilePath(const FilePath& database_path);
+  static base::FilePath GetJournalFilePath(const base::FilePath& database_path);
 
-  explicit DomStorageDatabase(const FilePath& file_path);
+  explicit DomStorageDatabase(const base::FilePath& file_path);
   virtual ~DomStorageDatabase();  // virtual for unit testing
 
   // Reads all the key, value pairs stored in the database and returns
@@ -41,7 +41,7 @@ class WEBKIT_STORAGE_EXPORT DomStorageDatabase {
   bool CommitChanges(bool clear_all_first, const ValuesMap& changes);
 
   // Simple getter for the path we were constructed with.
-  const FilePath& file_path() const { return file_path_; }
+  const base::FilePath& file_path() const { return file_path_; }
 
  protected:
   // Constructor that uses an in-memory sqlite database, for testing.
@@ -107,7 +107,7 @@ class WEBKIT_STORAGE_EXPORT DomStorageDatabase {
   void Init();
 
   // Path to the database on disk.
-  const FilePath file_path_;
+  const base::FilePath file_path_;
   scoped_ptr<sql::Connection> db_;
   bool failed_to_open_;
   bool tried_to_recreate_;
diff --git a/webkit/dom_storage/dom_storage_database_unittest.cc b/webkit/dom_storage/dom_storage_database_unittest.cc
index 3e9bfbddf997c2..79f8afbf51b5e0 100644
--- a/webkit/dom_storage/dom_storage_database_unittest.cc
+++ b/webkit/dom_storage/dom_storage_database_unittest.cc
@@ -110,7 +110,7 @@ TEST(DomStorageDatabaseTest, SimpleOpenAndClose) {
 TEST(DomStorageDatabaseTest, CloseEmptyDatabaseDeletesFile) {
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
+  base::FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
   ValuesMap storage;
   CreateMapWithValues(&storage);
 
@@ -167,7 +167,7 @@ TEST(DomStorageDatabaseTest, TestLazyOpenIsLazy) {
   // open a file that already exists when only invoking ReadAllValues.
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
+  base::FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
 
   DomStorageDatabase db(file_name);
   EXPECT_FALSE(db.IsOpen());
@@ -214,7 +214,7 @@ TEST(DomStorageDatabaseTest, TestLazyOpenUpgradesDatabase) {
   // early if the database is already open).
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
+  base::FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
 
   DomStorageDatabase db(file_name);
   db.db_.reset(new sql::Connection());
@@ -301,7 +301,7 @@ TEST(DomStorageDatabaseTest, TestSimpleRemoveOneValue) {
 }
 
 TEST(DomStorageDatabaseTest, TestCanOpenAndReadWebCoreDatabase) {
-  FilePath webcore_database;
+  base::FilePath webcore_database;
   PathService::Get(base::DIR_SOURCE_ROOT, &webcore_database);
   webcore_database = webcore_database.AppendASCII("webkit");
   webcore_database = webcore_database.AppendASCII("data");
@@ -334,7 +334,7 @@ TEST(DomStorageDatabaseTest, TestCanOpenFileThatIsNotADatabase) {
   // Write into the temporary file first.
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
-  FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
+  base::FilePath file_name = temp_dir.path().AppendASCII("TestDomStorageDatabase.db");
 
   const char kData[] = "I am not a database.";
   file_util::WriteFile(file_name, kData, strlen(kData));
diff --git a/webkit/dom_storage/dom_storage_namespace.cc b/webkit/dom_storage/dom_storage_namespace.cc
index ee91ca26d1232f..4c1cbd7466c638 100644
--- a/webkit/dom_storage/dom_storage_namespace.cc
+++ b/webkit/dom_storage/dom_storage_namespace.cc
@@ -16,7 +16,7 @@
 namespace dom_storage {
 
 DomStorageNamespace::DomStorageNamespace(
-    const FilePath& directory,
+    const base::FilePath& directory,
     DomStorageTaskRunner* task_runner)
     : namespace_id_(kLocalStorageNamespaceId),
       directory_(directory),
diff --git a/webkit/dom_storage/dom_storage_namespace.h b/webkit/dom_storage/dom_storage_namespace.h
index e1c72f09504556..00439c0d1b0596 100644
--- a/webkit/dom_storage/dom_storage_namespace.h
+++ b/webkit/dom_storage/dom_storage_namespace.h
@@ -27,7 +27,7 @@ class WEBKIT_STORAGE_EXPORT DomStorageNamespace
  public:
   // Constructor for a LocalStorage namespace with id of 0
   // and an optional backing directory on disk.
-  DomStorageNamespace(const FilePath& directory,  // may be empty
+  DomStorageNamespace(const base::FilePath& directory,  // may be empty
                       DomStorageTaskRunner* task_runner);
 
   // Constructor for a SessionStorage namespace with a non-zero id and an
@@ -83,7 +83,7 @@ class WEBKIT_STORAGE_EXPORT DomStorageNamespace
 
   int64 namespace_id_;
   std::string persistent_namespace_id_;
-  FilePath directory_;
+  base::FilePath directory_;
   AreaMap areas_;
   scoped_refptr<DomStorageTaskRunner> task_runner_;
   scoped_refptr<SessionStorageDatabase> session_storage_database_;
diff --git a/webkit/dom_storage/local_storage_database_adapter.cc b/webkit/dom_storage/local_storage_database_adapter.cc
index 6e715d73d9a000..32f724f8238bca 100644
--- a/webkit/dom_storage/local_storage_database_adapter.cc
+++ b/webkit/dom_storage/local_storage_database_adapter.cc
@@ -10,7 +10,7 @@
 namespace dom_storage {
 
 LocalStorageDatabaseAdapter::LocalStorageDatabaseAdapter(
-    const FilePath& path)
+    const base::FilePath& path)
     : db_(new DomStorageDatabase(path)) {
 }
 
diff --git a/webkit/dom_storage/local_storage_database_adapter.h b/webkit/dom_storage/local_storage_database_adapter.h
index f69e87b54298df..e9e646b71be9ed 100644
--- a/webkit/dom_storage/local_storage_database_adapter.h
+++ b/webkit/dom_storage/local_storage_database_adapter.h
@@ -10,7 +10,9 @@
 #include "webkit/dom_storage/dom_storage_database_adapter.h"
 #include "webkit/storage/webkit_storage_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace dom_storage {
 
@@ -19,7 +21,7 @@ class DomStorageDatabase;
 class WEBKIT_STORAGE_EXPORT LocalStorageDatabaseAdapter :
       public DomStorageDatabaseAdapter {
  public:
-  explicit LocalStorageDatabaseAdapter(const FilePath& path);
+  explicit LocalStorageDatabaseAdapter(const base::FilePath& path);
   virtual ~LocalStorageDatabaseAdapter();
   virtual void ReadAllValues(ValuesMap* result) OVERRIDE;
   virtual bool CommitChanges(bool clear_all_first,
diff --git a/webkit/dom_storage/session_storage_database.cc b/webkit/dom_storage/session_storage_database.cc
index 0f26f567227272..794473836ba4d2 100644
--- a/webkit/dom_storage/session_storage_database.cc
+++ b/webkit/dom_storage/session_storage_database.cc
@@ -36,7 +36,7 @@
 
 namespace dom_storage {
 
-SessionStorageDatabase::SessionStorageDatabase(const FilePath& file_path)
+SessionStorageDatabase::SessionStorageDatabase(const base::FilePath& file_path)
     : file_path_(file_path),
       db_error_(false),
       is_inconsistent_(false) {
diff --git a/webkit/dom_storage/session_storage_database.h b/webkit/dom_storage/session_storage_database.h
index c9fc813be20388..44ecb976796867 100644
--- a/webkit/dom_storage/session_storage_database.h
+++ b/webkit/dom_storage/session_storage_database.h
@@ -36,7 +36,7 @@ namespace dom_storage {
 class WEBKIT_STORAGE_EXPORT SessionStorageDatabase :
     public base::RefCountedThreadSafe<SessionStorageDatabase> {
  public:
-  explicit SessionStorageDatabase(const FilePath& file_path);
+  explicit SessionStorageDatabase(const base::FilePath& file_path);
 
   // Reads the (key, value) pairs for |namespace_id| and |origin|. |result| is
   // assumed to be empty and any duplicate keys will be overwritten. If the
@@ -187,7 +187,7 @@ class WEBKIT_STORAGE_EXPORT SessionStorageDatabase :
   static const char* NextMapIdKey();
 
   scoped_ptr<leveldb::DB> db_;
-  FilePath file_path_;
+  base::FilePath file_path_;
 
   // For protecting the database opening code.
   base::Lock db_lock_;
diff --git a/webkit/fileapi/async_file_util.h b/webkit/fileapi/async_file_util.h
index 651d0a518f4d5e..d00dc8245177ce 100644
--- a/webkit/fileapi/async_file_util.h
+++ b/webkit/fileapi/async_file_util.h
@@ -42,7 +42,7 @@ class WEBKIT_STORAGE_EXPORT AsyncFileUtil {
   typedef base::Callback<
       void(base::PlatformFileError result,
            const base::PlatformFileInfo& file_info,
-           const FilePath& platform_path)> GetFileInfoCallback;
+           const base::FilePath& platform_path)> GetFileInfoCallback;
 
   typedef base::FileUtilProxy::Entry Entry;
   typedef std::vector<base::FileUtilProxy::Entry> EntryList;
@@ -54,7 +54,7 @@ class WEBKIT_STORAGE_EXPORT AsyncFileUtil {
   typedef base::Callback<
       void(base::PlatformFileError result,
            const base::PlatformFileInfo& file_info,
-           const FilePath& platform_path,
+           const base::FilePath& platform_path,
            SnapshotFilePolicy policy)> CreateSnapshotFileCallback;
 
   AsyncFileUtil() {}
@@ -243,7 +243,7 @@ class WEBKIT_STORAGE_EXPORT AsyncFileUtil {
   //
   virtual bool CopyInForeignFile(
         FileSystemOperationContext* context,
-        const FilePath& src_file_path,
+        const base::FilePath& src_file_path,
         const FileSystemURL& dest_url,
         const StatusCallback& callback) = 0;
 
diff --git a/webkit/fileapi/async_file_util_adapter.cc b/webkit/fileapi/async_file_util_adapter.cc
index 4c6dca1ea8842a..0b9f2c8bdd593f 100644
--- a/webkit/fileapi/async_file_util_adapter.cc
+++ b/webkit/fileapi/async_file_util_adapter.cc
@@ -78,7 +78,7 @@ class GetFileInfoHelper {
  private:
   base::PlatformFileError error_;
   base::PlatformFileInfo file_info_;
-  FilePath platform_path_;
+  base::FilePath platform_path_;
   SnapshotFilePolicy snapshot_policy_;
   DISALLOW_COPY_AND_ASSIGN(GetFileInfoHelper);
 };
@@ -91,7 +91,7 @@ class ReadDirectoryHelper {
                FileSystemOperationContext* context,
                const FileSystemURL& url) {
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     PlatformFileError error = file_util->GetFileInfo(
         context, url, &file_info, &platform_path);
     if (error != base::PLATFORM_FILE_OK) {
@@ -106,7 +106,7 @@ class ReadDirectoryHelper {
     scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> file_enum(
         file_util->CreateFileEnumerator(context, url, false /* recursive */));
 
-    FilePath current;
+    base::FilePath current;
     while (!(current = file_enum->Next()).empty()) {
       AsyncFileUtil::Entry entry;
       entry.is_directory = file_enum->IsDirectory();
@@ -257,7 +257,7 @@ bool AsyncFileUtilAdapter::MoveFileLocal(
 
 bool AsyncFileUtilAdapter::CopyInForeignFile(
       FileSystemOperationContext* context,
-      const FilePath& src_file_path,
+      const base::FilePath& src_file_path,
       const FileSystemURL& dest_url,
       const StatusCallback& callback) {
   return base::PostTaskAndReplyWithResult(
diff --git a/webkit/fileapi/async_file_util_adapter.h b/webkit/fileapi/async_file_util_adapter.h
index da8bb4c0f3a490..065354d4b6fcf5 100644
--- a/webkit/fileapi/async_file_util_adapter.h
+++ b/webkit/fileapi/async_file_util_adapter.h
@@ -82,7 +82,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE AsyncFileUtilAdapter
       const StatusCallback& callback) OVERRIDE;
   virtual bool CopyInForeignFile(
         FileSystemOperationContext* context,
-        const FilePath& src_file_path,
+        const base::FilePath& src_file_path,
         const FileSystemURL& dest_url,
         const StatusCallback& callback) OVERRIDE;
   virtual bool DeleteFile(
diff --git a/webkit/fileapi/cross_operation_delegate.cc b/webkit/fileapi/cross_operation_delegate.cc
index 86868e24b62d81..28bd6da77703fe 100644
--- a/webkit/fileapi/cross_operation_delegate.cc
+++ b/webkit/fileapi/cross_operation_delegate.cc
@@ -169,7 +169,7 @@ void CrossOperationDelegate::DidCreateSnapshot(
     const StatusCallback& callback,
     base::PlatformFileError error,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path,
+    const base::FilePath& platform_path,
     const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref) {
   if (error != base::PLATFORM_FILE_OK) {
     callback.Run(error);
@@ -222,7 +222,7 @@ FileSystemURL CrossOperationDelegate::CreateDestURL(
   DCHECK_EQ(src_root_.type(), src_url.type());
   DCHECK_EQ(src_root_.origin(), src_url.origin());
 
-  FilePath path = dest_root_.path();
+  base::FilePath path = dest_root_.path();
   src_root_.path().AppendRelativePath(src_url.path(), &path);
   return dest_root_.WithPath(path);
 }
diff --git a/webkit/fileapi/cross_operation_delegate.h b/webkit/fileapi/cross_operation_delegate.h
index 1b169f77d83384..3be003a0bbd796 100644
--- a/webkit/fileapi/cross_operation_delegate.h
+++ b/webkit/fileapi/cross_operation_delegate.h
@@ -55,7 +55,7 @@ class CrossOperationDelegate
       const StatusCallback& callback,
       base::PlatformFileError error,
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
   void DidFinishCopy(
       const FileSystemURL& src,
diff --git a/webkit/fileapi/external_mount_points.cc b/webkit/fileapi/external_mount_points.cc
index bca5b2ba496ac6..b129911695ebf3 100644
--- a/webkit/fileapi/external_mount_points.cc
+++ b/webkit/fileapi/external_mount_points.cc
@@ -20,15 +20,15 @@ namespace {
 // For example, /a/b/c(1)/d would be erroneously resolved as c/d if the
 // following mount points were registered: "/a/b/c", "/a/b/c(1)". (Note:
 // "/a/b/c" < "/a/b/c(1)" < "/a/b/c/").
-FilePath NormalizeFilePath(const FilePath& path) {
+base::FilePath NormalizeFilePath(const base::FilePath& path) {
   if (path.empty())
     return path;
 
-  FilePath::StringType path_str = path.StripTrailingSeparators().value();
-  if (!FilePath::IsSeparator(path_str[path_str.length() - 1]))
+  base::FilePath::StringType path_str = path.StripTrailingSeparators().value();
+  if (!base::FilePath::IsSeparator(path_str[path_str.length() - 1]))
     path_str.append(FILE_PATH_LITERAL("/"));
 
-  return FilePath(path_str).NormalizePathSeparators();
+  return base::FilePath(path_str).NormalizePathSeparators();
 }
 
 // Wrapper around ref-counted ExternalMountPoints that will be used to lazily
@@ -53,15 +53,15 @@ class SystemMountPointsLazyWrapper {
     system_mount_points_->RegisterFileSystem(
         "archive",
         fileapi::kFileSystemTypeNativeLocal,
-        FilePath(FILE_PATH_LITERAL("/media/archive")));
+        base::FilePath(FILE_PATH_LITERAL("/media/archive")));
     system_mount_points_->RegisterFileSystem(
         "removable",
         fileapi::kFileSystemTypeNativeLocal,
-        FilePath(FILE_PATH_LITERAL("/media/removable")));
+        base::FilePath(FILE_PATH_LITERAL("/media/removable")));
     system_mount_points_->RegisterFileSystem(
         "oem",
         fileapi::kFileSystemTypeRestrictedNativeLocal,
-        FilePath(FILE_PATH_LITERAL("/usr/share/oem")));
+        base::FilePath(FILE_PATH_LITERAL("/usr/share/oem")));
 #endif  // defined(OS_CHROMEOS)
   }
 
@@ -78,20 +78,20 @@ namespace fileapi {
 class ExternalMountPoints::Instance {
  public:
   Instance(FileSystemType type,
-           const FilePath& path,
+           const base::FilePath& path,
            RemoteFileSystemProxyInterface* remote_proxy);
 
   ~Instance();
 
   FileSystemType type() const { return type_; }
-  const FilePath& path() const { return path_; }
+  const base::FilePath& path() const { return path_; }
   RemoteFileSystemProxyInterface* remote_proxy() const {
     return remote_proxy_.get();
   }
 
  private:
   const FileSystemType type_;
-  const FilePath path_;
+  const base::FilePath path_;
 
   // For file systems that have a remote file system proxy.
   scoped_refptr<RemoteFileSystemProxyInterface> remote_proxy_;
@@ -100,7 +100,7 @@ class ExternalMountPoints::Instance {
 };
 
 ExternalMountPoints::Instance::Instance(FileSystemType type,
-                                        const FilePath& path,
+                                        const base::FilePath& path,
                                         RemoteFileSystemProxyInterface* proxy)
     : type_(type),
       path_(path.StripTrailingSeparators()),
@@ -125,7 +125,7 @@ scoped_refptr<ExternalMountPoints> ExternalMountPoints::CreateRefCounted() {
 bool ExternalMountPoints::RegisterFileSystem(
     const std::string& mount_name,
     FileSystemType type,
-    const FilePath& path) {
+    const base::FilePath& path) {
   return RegisterRemoteFileSystem(mount_name, type, NULL, path);
 }
 
@@ -133,10 +133,10 @@ bool ExternalMountPoints::RegisterRemoteFileSystem(
     const std::string& mount_name,
     FileSystemType type,
     RemoteFileSystemProxyInterface* remote_proxy,
-    const FilePath& path_in) {
+    const base::FilePath& path_in) {
   base::AutoLock locker(lock_);
 
-  FilePath path = NormalizeFilePath(path_in);
+  base::FilePath path = NormalizeFilePath(path_in);
   if (!ValidateNewMountPoint(mount_name, path))
     return false;
 
@@ -164,7 +164,7 @@ bool ExternalMountPoints::RevokeFileSystem(const std::string& mount_name) {
 }
 
 bool ExternalMountPoints::GetRegisteredPath(
-    const std::string& filesystem_id, FilePath* path) const {
+    const std::string& filesystem_id, base::FilePath* path) const {
   DCHECK(path);
   base::AutoLock locker(lock_);
   NameToInstance::const_iterator found = instance_map_.find(filesystem_id);
@@ -174,10 +174,10 @@ bool ExternalMountPoints::GetRegisteredPath(
   return true;
 }
 
-bool ExternalMountPoints::CrackVirtualPath(const FilePath& virtual_path,
+bool ExternalMountPoints::CrackVirtualPath(const base::FilePath& virtual_path,
                                            std::string* mount_name,
                                            FileSystemType* type,
-                                           FilePath* path) const {
+                                           base::FilePath* path) const {
   DCHECK(mount_name);
   DCHECK(path);
 
@@ -186,18 +186,18 @@ bool ExternalMountPoints::CrackVirtualPath(const FilePath& virtual_path,
     return false;
 
   // The virtual_path should comprise of <mount_name> and <relative_path> parts.
-  std::vector<FilePath::StringType> components;
+  std::vector<base::FilePath::StringType> components;
   virtual_path.GetComponents(&components);
   if (components.size() < 1)
     return false;
 
-  std::vector<FilePath::StringType>::iterator component_iter =
+  std::vector<base::FilePath::StringType>::iterator component_iter =
       components.begin();
-  std::string maybe_mount_name = FilePath(*component_iter++).MaybeAsASCII();
+  std::string maybe_mount_name = base::FilePath(*component_iter++).MaybeAsASCII();
   if (maybe_mount_name.empty())
     return false;
 
-  FilePath cracked_path;
+  base::FilePath cracked_path;
   {
     base::AutoLock locker(lock_);
     NameToInstance::const_iterator found_instance =
@@ -230,13 +230,13 @@ FileSystemURL ExternalMountPoints::CrackURL(const GURL& url) const {
 FileSystemURL ExternalMountPoints::CreateCrackedFileSystemURL(
     const GURL& origin,
     FileSystemType type,
-    const FilePath& path) const {
+    const base::FilePath& path) const {
   if (!HandlesFileSystemMountType(type))
     return FileSystemURL();
 
   std::string mount_name;
   FileSystemType cracked_type;
-  FilePath cracked_path;
+  base::FilePath cracked_path;
   if (!CrackVirtualPath(path, &mount_name, &cracked_type, &cracked_path))
     return FileSystemURL();
 
@@ -263,14 +263,14 @@ void ExternalMountPoints::AddMountPointInfosTo(
   }
 }
 
-bool ExternalMountPoints::GetVirtualPath(const FilePath& path_in,
-                                         FilePath* virtual_path) {
+bool ExternalMountPoints::GetVirtualPath(const base::FilePath& path_in,
+                                         base::FilePath* virtual_path) {
   DCHECK(virtual_path);
 
   base::AutoLock locker(lock_);
 
-  FilePath path = NormalizeFilePath(path_in);
-  std::map<FilePath, std::string>::reverse_iterator iter(
+  base::FilePath path = NormalizeFilePath(path_in);
+  std::map<base::FilePath, std::string>::reverse_iterator iter(
       path_to_name_map_.upper_bound(path));
   if (iter == path_to_name_map_.rend())
     return false;
@@ -281,9 +281,9 @@ bool ExternalMountPoints::GetVirtualPath(const FilePath& path_in,
   return iter->first.AppendRelativePath(path, virtual_path);
 }
 
-FilePath ExternalMountPoints::CreateVirtualRootPath(
+base::FilePath ExternalMountPoints::CreateVirtualRootPath(
     const std::string& mount_name) const {
-  return FilePath().AppendASCII(mount_name);
+  return base::FilePath().AppendASCII(mount_name);
 }
 
 ExternalMountPoints::ExternalMountPoints() {}
@@ -294,7 +294,7 @@ ExternalMountPoints::~ExternalMountPoints() {
 }
 
 bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
-                                                const FilePath& path) {
+                                                const base::FilePath& path) {
   lock_.AssertAcquired();
 
   // Mount name must not be empty.
@@ -315,7 +315,7 @@ bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
     return false;
 
   // Check there the new path does not overlap with one of the existing ones.
-  std::map<FilePath, std::string>::reverse_iterator potential_parent(
+  std::map<base::FilePath, std::string>::reverse_iterator potential_parent(
       path_to_name_map_.upper_bound(path));
   if (potential_parent != path_to_name_map_.rend()) {
     if (potential_parent->first == path ||
@@ -324,7 +324,7 @@ bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
     }
   }
 
-  std::map<FilePath, std::string>::iterator potential_child =
+  std::map<base::FilePath, std::string>::iterator potential_child =
       path_to_name_map_.upper_bound(path);
   if (potential_child == path_to_name_map_.end())
     return true;
@@ -335,13 +335,13 @@ bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
 ScopedExternalFileSystem::ScopedExternalFileSystem(
     const std::string& mount_name,
     FileSystemType type,
-    const FilePath& path)
+    const base::FilePath& path)
     : mount_name_(mount_name) {
   ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
       mount_name, type, path);
 }
 
-FilePath ScopedExternalFileSystem::GetVirtualRootPath() const {
+base::FilePath ScopedExternalFileSystem::GetVirtualRootPath() const {
   return ExternalMountPoints::GetSystemInstance()->
       CreateVirtualRootPath(mount_name_);
 }
diff --git a/webkit/fileapi/external_mount_points.h b/webkit/fileapi/external_mount_points.h
index f2d8e29198480e..a2660c24536d11 100644
--- a/webkit/fileapi/external_mount_points.h
+++ b/webkit/fileapi/external_mount_points.h
@@ -15,7 +15,9 @@
 #include "webkit/fileapi/mount_points.h"
 #include "webkit/storage/webkit_storage_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace fileapi {
 class FileSystemURL;
@@ -60,29 +62,29 @@ class WEBKIT_STORAGE_EXPORT ExternalMountPoints
   // by calling RevokeFileSystem with |mount_name|.
   bool RegisterFileSystem(const std::string& mount_name,
                           FileSystemType type,
-                          const FilePath& path);
+                          const base::FilePath& path);
 
   // Same as |RegisterExternalFileSystem|, but also registers a remote file
   // system proxy for the file system.
   bool RegisterRemoteFileSystem(const std::string& mount_name,
                                 FileSystemType type,
                                 RemoteFileSystemProxyInterface* remote_proxy,
-                                const FilePath& path);
+                                const base::FilePath& path);
 
   // MountPoints overrides.
   virtual bool HandlesFileSystemMountType(FileSystemType type) const OVERRIDE;
   virtual bool RevokeFileSystem(const std::string& mount_name) OVERRIDE;
   virtual bool GetRegisteredPath(const std::string& mount_name,
-                                 FilePath* path) const OVERRIDE;
-  virtual bool CrackVirtualPath(const FilePath& virtual_path,
+                                 base::FilePath* path) const OVERRIDE;
+  virtual bool CrackVirtualPath(const base::FilePath& virtual_path,
                                 std::string* mount_name,
                                 FileSystemType* type,
-                                FilePath* path) const OVERRIDE;
+                                base::FilePath* path) const OVERRIDE;
   virtual FileSystemURL CrackURL(const GURL& url) const OVERRIDE;
   virtual FileSystemURL CreateCrackedFileSystemURL(
       const GURL& origin,
       FileSystemType type,
-      const FilePath& path) const OVERRIDE;
+      const base::FilePath& path) const OVERRIDE;
 
   // Retrieves the remote file system proxy for the registered file system.
   // Returns NULL if there is no file system with the given name, or if the file
@@ -102,10 +104,11 @@ class WEBKIT_STORAGE_EXPORT ExternalMountPoints
   // part of any registered filesystem).
   //
   // Returned virtual_path will have normalized path separators.
-  bool GetVirtualPath(const FilePath& absolute_path, FilePath* virtual_path);
+  bool GetVirtualPath(const base::FilePath& absolute_path,
+                      base::FilePath* virtual_path);
 
   // Returns the virtual root path that looks like /<mount_name>.
-  FilePath CreateVirtualRootPath(const std::string& mount_name) const;
+  base::FilePath CreateVirtualRootPath(const std::string& mount_name) const;
 
  private:
   friend class base::RefCountedThreadSafe<ExternalMountPoints>;
@@ -116,7 +119,7 @@ class WEBKIT_STORAGE_EXPORT ExternalMountPoints
   typedef std::map<std::string, Instance*> NameToInstance;
 
   // Reverse map from registered path to its corresponding mount name.
-  typedef std::map<FilePath, std::string> PathToName;
+  typedef std::map<base::FilePath, std::string> PathToName;
 
   // Use |GetSystemInstance| of |CreateRefCounted| to get an instance.
   ExternalMountPoints();
@@ -131,7 +134,7 @@ class WEBKIT_STORAGE_EXPORT ExternalMountPoints
   //
   // |lock_| should be taken before calling this method.
   bool ValidateNewMountPoint(const std::string& mount_name,
-                             const FilePath& path);
+                             const base::FilePath& path);
 
   // This lock needs to be obtained when accessing the instance_map_.
   mutable base::Lock lock_;
@@ -147,10 +150,10 @@ class WEBKIT_STORAGE_EXPORT ScopedExternalFileSystem {
  public:
   ScopedExternalFileSystem(const std::string& mount_name,
                            FileSystemType type,
-                           const FilePath& path);
+                           const base::FilePath& path);
   ~ScopedExternalFileSystem();
 
-  FilePath GetVirtualRootPath() const;
+  base::FilePath GetVirtualRootPath() const;
 
  private:
   const std::string mount_name_;
diff --git a/webkit/fileapi/external_mount_points_unittest.cc b/webkit/fileapi/external_mount_points_unittest.cc
index 4668264a166a56..c8edbdde161d08 100644
--- a/webkit/fileapi/external_mount_points_unittest.cc
+++ b/webkit/fileapi/external_mount_points_unittest.cc
@@ -30,12 +30,12 @@ TEST(ExternalMountPointsTest, AddMountPoint) {
     // The mount point's name.
     const char* const name;
     // The mount point's path.
-    const FilePath::CharType* const path;
+    const base::FilePath::CharType* const path;
     // Whether the mount point registration should succeed.
     bool success;
     // Path returned by GetRegisteredPath. NULL if the method is expected to
     // fail.
-    const FilePath::CharType* const registered_path;
+    const base::FilePath::CharType* const registered_path;
   };
 
   const TestCase kTestCases[] = {
@@ -111,20 +111,20 @@ TEST(ExternalMountPointsTest, AddMountPoint) {
               mount_points->RegisterFileSystem(
                   kTestCases[i].name,
                   fileapi::kFileSystemTypeNativeLocal,
-                  FilePath(kTestCases[i].path)))
+                  base::FilePath(kTestCases[i].path)))
         << "Adding mount point: " << kTestCases[i].name << " with path "
         << kTestCases[i].path;
   }
 
   // Test that final mount point presence state is as expected.
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kTestCases); ++i) {
-    FilePath found_path;
+    base::FilePath found_path;
     EXPECT_EQ(kTestCases[i].registered_path != NULL,
               mount_points->GetRegisteredPath(kTestCases[i].name, &found_path))
         << "Test case: " << i;
 
     if (kTestCases[i].registered_path) {
-      FilePath expected_path(kTestCases[i].registered_path);
+      base::FilePath expected_path(kTestCases[i].registered_path);
       EXPECT_EQ(expected_path.NormalizePathSeparators(), found_path);
     }
   }
@@ -136,30 +136,30 @@ TEST(ExternalMountPointsTest, GetVirtualPath) {
 
   mount_points->RegisterFileSystem("c",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/a/b/c")));
+                                   base::FilePath(DRIVE FPL("/a/b/c")));
   // Note that "/a/b/c" < "/a/b/c(1)" < "/a/b/c/".
   mount_points->RegisterFileSystem("c(1)",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/a/b/c(1)")));
+                                   base::FilePath(DRIVE FPL("/a/b/c(1)")));
   mount_points->RegisterFileSystem("x",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/z/y/x")));
+                                   base::FilePath(DRIVE FPL("/z/y/x")));
   mount_points->RegisterFileSystem("o",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/m/n/o")));
+                                   base::FilePath(DRIVE FPL("/m/n/o")));
   // A mount point whose name does not match its path base name.
   mount_points->RegisterFileSystem("mount",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/root/foo")));
+                                   base::FilePath(DRIVE FPL("/root/foo")));
   // A mount point with an empty path.
   mount_points->RegisterFileSystem("empty_path",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(FPL("")));
+                                   base::FilePath(FPL("")));
 
   struct TestCase {
-    const FilePath::CharType* const local_path;
+    const base::FilePath::CharType* const local_path;
     bool success;
-    const FilePath::CharType* const virtual_path;
+    const base::FilePath::CharType* const virtual_path;
   };
 
   const TestCase kTestCases[] = {
@@ -209,8 +209,8 @@ TEST(ExternalMountPointsTest, GetVirtualPath) {
 
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kTestCases); ++i) {
     // Initialize virtual path with a value.
-    FilePath virtual_path(DRIVE FPL("/mount"));
-    FilePath local_path(kTestCases[i].local_path);
+    base::FilePath virtual_path(DRIVE FPL("/mount"));
+    base::FilePath local_path(kTestCases[i].local_path);
     EXPECT_EQ(kTestCases[i].success,
               mount_points->GetVirtualPath(local_path, &virtual_path))
         << "Resolving " << kTestCases[i].local_path;
@@ -220,7 +220,7 @@ TEST(ExternalMountPointsTest, GetVirtualPath) {
     if (!kTestCases[i].success)
       continue;
 
-    FilePath expected_virtual_path(kTestCases[i].virtual_path);
+    base::FilePath expected_virtual_path(kTestCases[i].virtual_path);
     EXPECT_EQ(expected_virtual_path.NormalizePathSeparators(), virtual_path)
         << "Resolving " << kTestCases[i].local_path;
   }
@@ -231,7 +231,7 @@ TEST(ExternalMountPointsTest, HandlesFileSystemMountType) {
       fileapi::ExternalMountPoints::CreateRefCounted());
 
   const GURL test_origin("http://chromium.org");
-  const FilePath test_path(FPL("/mount"));
+  const base::FilePath test_path(FPL("/mount"));
 
   // Should handle External File System.
   EXPECT_TRUE(mount_points->HandlesFileSystemMountType(
@@ -265,16 +265,16 @@ TEST(ExternalMountPointsTest, CreateCrackedFileSystemURL) {
 
   mount_points->RegisterFileSystem("c",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/a/b/c")));
+                                   base::FilePath(DRIVE FPL("/a/b/c")));
   mount_points->RegisterFileSystem("c(1)",
                                    fileapi::kFileSystemTypeDrive,
-                                   FilePath(DRIVE FPL("/a/b/c(1)")));
+                                   base::FilePath(DRIVE FPL("/a/b/c(1)")));
   mount_points->RegisterFileSystem("empty_path",
                                    fileapi::kFileSystemTypeSyncable,
-                                   FilePath(FPL("")));
+                                   base::FilePath(FPL("")));
   mount_points->RegisterFileSystem("mount",
                                    fileapi::kFileSystemTypeDrive,
-                                   FilePath(DRIVE FPL("/root")));
+                                   base::FilePath(DRIVE FPL("/root")));
 
   // Try cracking invalid GURL.
   FileSystemURL invalid = mount_points->CrackURL(GURL("http://chromium.og"));
@@ -282,19 +282,19 @@ TEST(ExternalMountPointsTest, CreateCrackedFileSystemURL) {
 
   // Try cracking isolated path.
   FileSystemURL isolated = mount_points->CreateCrackedFileSystemURL(
-      kTestOrigin, fileapi::kFileSystemTypeIsolated, FilePath(FPL("c")));
+      kTestOrigin, fileapi::kFileSystemTypeIsolated, base::FilePath(FPL("c")));
   EXPECT_FALSE(isolated.is_valid());
 
   // Try native local which is not cracked.
   FileSystemURL native_local = mount_points->CreateCrackedFileSystemURL(
-      kTestOrigin, fileapi::kFileSystemTypeNativeLocal, FilePath(FPL("c")));
+      kTestOrigin, fileapi::kFileSystemTypeNativeLocal, base::FilePath(FPL("c")));
   EXPECT_FALSE(native_local.is_valid());
 
   struct TestCase {
-    const FilePath::CharType* const path;
+    const base::FilePath::CharType* const path;
     bool expect_valid;
     fileapi::FileSystemType expect_type;
-    const FilePath::CharType* const expect_path;
+    const base::FilePath::CharType* const expect_path;
     const char* const expect_fs_id;
   };
 
@@ -343,7 +343,7 @@ TEST(ExternalMountPointsTest, CreateCrackedFileSystemURL) {
     FileSystemURL cracked = mount_points->CreateCrackedFileSystemURL(
         kTestOrigin,
         fileapi::kFileSystemTypeExternal,
-        FilePath(kTestCases[i].path));
+        base::FilePath(kTestCases[i].path));
 
     EXPECT_EQ(kTestCases[i].expect_valid, cracked.is_valid())
         << "Test case index: " << i;
@@ -355,10 +355,10 @@ TEST(ExternalMountPointsTest, CreateCrackedFileSystemURL) {
         << "Test case index: " << i;
     EXPECT_EQ(kTestCases[i].expect_type, cracked.type())
         << "Test case index: " << i;
-    EXPECT_EQ(FilePath(kTestCases[i].expect_path).NormalizePathSeparators(),
+    EXPECT_EQ(base::FilePath(kTestCases[i].expect_path).NormalizePathSeparators(),
                        cracked.path())
         << "Test case index: " << i;
-    EXPECT_EQ(FilePath(kTestCases[i].path).NormalizePathSeparators(),
+    EXPECT_EQ(base::FilePath(kTestCases[i].path).NormalizePathSeparators(),
                        cracked.virtual_path())
         << "Test case index: " << i;
     EXPECT_EQ(kTestCases[i].expect_fs_id, cracked.filesystem_id())
@@ -376,22 +376,22 @@ TEST(ExternalMountPointsTest, CrackVirtualPath) {
 
   mount_points->RegisterFileSystem("c",
                                    fileapi::kFileSystemTypeNativeLocal,
-                                   FilePath(DRIVE FPL("/a/b/c")));
+                                   base::FilePath(DRIVE FPL("/a/b/c")));
   mount_points->RegisterFileSystem("c(1)",
                                    fileapi::kFileSystemTypeDrive,
-                                   FilePath(DRIVE FPL("/a/b/c(1)")));
+                                   base::FilePath(DRIVE FPL("/a/b/c(1)")));
   mount_points->RegisterFileSystem("empty_path",
                                    fileapi::kFileSystemTypeSyncable,
-                                   FilePath(FPL("")));
+                                   base::FilePath(FPL("")));
   mount_points->RegisterFileSystem("mount",
                                    fileapi::kFileSystemTypeDrive,
-                                   FilePath(DRIVE FPL("/root")));
+                                   base::FilePath(DRIVE FPL("/root")));
 
   struct TestCase {
-    const FilePath::CharType* const path;
+    const base::FilePath::CharType* const path;
     bool expect_valid;
     fileapi::FileSystemType expect_type;
-    const FilePath::CharType* const expect_path;
+    const base::FilePath::CharType* const expect_path;
     const char* const expect_name;
   };
 
@@ -439,9 +439,9 @@ TEST(ExternalMountPointsTest, CrackVirtualPath) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kTestCases); ++i) {
     std::string cracked_name;
     fileapi::FileSystemType cracked_type;
-    FilePath cracked_path;
+    base::FilePath cracked_path;
     EXPECT_EQ(kTestCases[i].expect_valid,
-              mount_points->CrackVirtualPath(FilePath(kTestCases[i].path),
+              mount_points->CrackVirtualPath(base::FilePath(kTestCases[i].path),
                   &cracked_name, &cracked_type, &cracked_path))
         << "Test case index: " << i;
 
@@ -450,7 +450,7 @@ TEST(ExternalMountPointsTest, CrackVirtualPath) {
 
     EXPECT_EQ(kTestCases[i].expect_type, cracked_type)
         << "Test case index: " << i;
-    EXPECT_EQ(FilePath(kTestCases[i].expect_path).NormalizePathSeparators(),
+    EXPECT_EQ(base::FilePath(kTestCases[i].expect_path).NormalizePathSeparators(),
                        cracked_path)
         << "Test case index: " << i;
     EXPECT_EQ(kTestCases[i].expect_name, cracked_name)
diff --git a/webkit/fileapi/file_system_callback_dispatcher.h b/webkit/fileapi/file_system_callback_dispatcher.h
index af0a757bdb50fa..990e6332d2d319 100644
--- a/webkit/fileapi/file_system_callback_dispatcher.h
+++ b/webkit/fileapi/file_system_callback_dispatcher.h
@@ -30,7 +30,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemCallbackDispatcher {
   // Callback to report information for a file.
   virtual void DidReadMetadata(
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path) = 0;
+      const base::FilePath& platform_path) = 0;
 
   // Callback to report the contents of a directory. If the contents of
   // the given directory are reported in one batch, then |entries| will have
diff --git a/webkit/fileapi/file_system_context.cc b/webkit/fileapi/file_system_context.cc
index 67cbc6dce6b69c..ab8c92953dfea4 100644
--- a/webkit/fileapi/file_system_context.cc
+++ b/webkit/fileapi/file_system_context.cc
@@ -58,7 +58,7 @@ FileSystemContext::FileSystemContext(
     ExternalMountPoints* external_mount_points,
     quota::SpecialStoragePolicy* special_storage_policy,
     quota::QuotaManagerProxy* quota_manager_proxy,
-    const FilePath& partition_path,
+    const base::FilePath& partition_path,
     const FileSystemOptions& options)
     : task_runners_(task_runners.Pass()),
       quota_manager_proxy_(quota_manager_proxy),
@@ -322,7 +322,7 @@ FileSystemURL FileSystemContext::CrackURL(const GURL& url) const {
 FileSystemURL FileSystemContext::CreateCrackedFileSystemURL(
     const GURL& origin,
     FileSystemType type,
-    const FilePath& path) const {
+    const base::FilePath& path) const {
   return CrackFileSystemURL(FileSystemURL(origin, type, path));
 }
 
diff --git a/webkit/fileapi/file_system_context.h b/webkit/fileapi/file_system_context.h
index c5db158f5e0c57..ec9fc6e16e60b2 100644
--- a/webkit/fileapi/file_system_context.h
+++ b/webkit/fileapi/file_system_context.h
@@ -19,7 +19,9 @@
 #include "webkit/fileapi/task_runner_bound_observer_list.h"
 #include "webkit/storage/webkit_storage_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace quota {
 class QuotaManagerProxy;
@@ -75,7 +77,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
       ExternalMountPoints* external_mount_points,
       quota::SpecialStoragePolicy* special_storage_policy,
       quota::QuotaManagerProxy* quota_manager_proxy,
-      const FilePath& partition_path,
+      const base::FilePath& partition_path,
       const FileSystemOptions& options);
 
   bool DeleteDataForOriginOnFileThread(const GURL& origin_url);
@@ -186,7 +188,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   LocalFileSyncContext* sync_context() { return sync_context_.get(); }
   void set_sync_context(LocalFileSyncContext* sync_context);
 
-  const FilePath& partition_path() const { return partition_path_; }
+  const base::FilePath& partition_path() const { return partition_path_; }
 
   // Same as |CrackFileSystemURL|, but cracks FileSystemURL created from |url|.
   FileSystemURL CrackURL(const GURL& url) const;
@@ -194,7 +196,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   // arguments.
   FileSystemURL CreateCrackedFileSystemURL(const GURL& origin,
                                            FileSystemType type,
-                                           const FilePath& path) const;
+                                           const base::FilePath& path) const;
 
  private:
   // Friended for GetFileUtil.
@@ -257,7 +259,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   std::vector<MountPoints*> url_crackers_;
 
   // The base path of the storage partition for this context.
-  const FilePath partition_path_;
+  const base::FilePath partition_path_;
 
   // For syncable file systems.
   scoped_ptr<LocalFileChangeTracker> change_tracker_;
diff --git a/webkit/fileapi/file_system_context_unittest.cc b/webkit/fileapi/file_system_context_unittest.cc
index 515563689161aa..0c135014cdaaf2 100644
--- a/webkit/fileapi/file_system_context_unittest.cc
+++ b/webkit/fileapi/file_system_context_unittest.cc
@@ -28,7 +28,7 @@ namespace fileapi {
 namespace {
 
 const char kTestOrigin[] = "http://chromium.org/";
-const FilePath::CharType kVirtualPathNoRoot[] = FPL("root/file");
+const base::FilePath::CharType kVirtualPathNoRoot[] = FPL("root/file");
 
 GURL CreateRawFileSystemURL(const std::string& type_str,
                             const std::string& fs_id) {
@@ -73,8 +73,8 @@ class FileSystemContextTest : public testing::Test {
                                   const GURL& expect_origin,
                                   FileSystemType expect_mount_type,
                                   FileSystemType expect_type,
-                                  const FilePath& expect_path,
-                                  const FilePath& expect_virtual_path,
+                                  const base::FilePath& expect_path,
+                                  const base::FilePath& expect_virtual_path,
                                   const std::string& expect_filesystem_id) {
     EXPECT_TRUE(url.is_valid());
 
@@ -105,13 +105,13 @@ TEST_F(FileSystemContextTest, NullExternalMountPoints) {
   std::string isolated_id =
       IsolatedContext::GetInstance()->RegisterFileSystemForPath(
           kFileSystemTypeNativeLocal,
-          FilePath(DRIVE FPL("/test/isolated/root")),
+          base::FilePath(DRIVE FPL("/test/isolated/root")),
           &isolated_name);
   // Register system external mount point.
   ASSERT_TRUE(ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
       "system",
       kFileSystemTypeNativeLocal,
-      FilePath(DRIVE FPL("/test/sys/"))));
+      base::FilePath(DRIVE FPL("/test/sys/"))));
 
   FileSystemURL cracked_isolated = file_system_context->CrackURL(
       CreateRawFileSystemURL("isolated", isolated_id));
@@ -121,8 +121,8 @@ TEST_F(FileSystemContextTest, NullExternalMountPoints) {
       GURL(kTestOrigin),
       kFileSystemTypeIsolated,
       kFileSystemTypeNativeLocal,
-      FilePath(DRIVE FPL("/test/isolated/root/file")).NormalizePathSeparators(),
-      FilePath::FromUTF8Unsafe(isolated_id).Append(FPL("root/file")).
+      base::FilePath(DRIVE FPL("/test/isolated/root/file")).NormalizePathSeparators(),
+      base::FilePath::FromUTF8Unsafe(isolated_id).Append(FPL("root/file")).
           NormalizePathSeparators(),
       isolated_id);
 
@@ -134,8 +134,8 @@ TEST_F(FileSystemContextTest, NullExternalMountPoints) {
       GURL(kTestOrigin),
       kFileSystemTypeExternal,
       kFileSystemTypeNativeLocal,
-      FilePath(DRIVE FPL("/test/sys/root/file")).NormalizePathSeparators(),
-      FilePath(FPL("system/root/file")).NormalizePathSeparators(),
+      base::FilePath(DRIVE FPL("/test/sys/root/file")).NormalizePathSeparators(),
+      base::FilePath(FPL("system/root/file")).NormalizePathSeparators(),
       "system");
 
 
@@ -152,7 +152,7 @@ TEST_F(FileSystemContextTest, FileSystemContextKeepsMountPointsAlive) {
   ASSERT_TRUE(mount_points->RegisterFileSystem(
       "system",
       kFileSystemTypeNativeLocal,
-      FilePath(DRIVE FPL("/test/sys/"))));
+      base::FilePath(DRIVE FPL("/test/sys/"))));
 
   scoped_refptr<FileSystemContext> file_system_context(
       CreateFileSystemContextForTest(mount_points.get()));
@@ -170,8 +170,8 @@ TEST_F(FileSystemContextTest, FileSystemContextKeepsMountPointsAlive) {
       GURL(kTestOrigin),
       kFileSystemTypeExternal,
       kFileSystemTypeNativeLocal,
-      FilePath(DRIVE FPL("/test/sys/root/file")).NormalizePathSeparators(),
-      FilePath(FPL("system/root/file")).NormalizePathSeparators(),
+      base::FilePath(DRIVE FPL("/test/sys/root/file")).NormalizePathSeparators(),
+      base::FilePath(FPL("system/root/file")).NormalizePathSeparators(),
       "system");
 
   // No need to revoke the registered filesystem since |mount_points| lifetime
@@ -189,32 +189,32 @@ TEST_F(FileSystemContextTest, CrackFileSystemURL) {
   const std::string kIsolatedFileSystemID =
       IsolatedContext::GetInstance()->RegisterFileSystemForPath(
           kFileSystemTypeNativeLocal,
-          FilePath(DRIVE FPL("/test/isolated/root")),
+          base::FilePath(DRIVE FPL("/test/isolated/root")),
           &isolated_file_system_name);
   // Register system external mount point.
   ASSERT_TRUE(ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
       "system",
       kFileSystemTypeDrive,
-      FilePath(DRIVE FPL("/test/sys/"))));
+      base::FilePath(DRIVE FPL("/test/sys/"))));
   ASSERT_TRUE(ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
       "ext",
       kFileSystemTypeNativeLocal,
-      FilePath(DRIVE FPL("/test/ext"))));
+      base::FilePath(DRIVE FPL("/test/ext"))));
   // Register a system external mount point with the same name/id as the
   // registered isolated mount point.
   ASSERT_TRUE(ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
       kIsolatedFileSystemID,
       kFileSystemTypeRestrictedNativeLocal,
-      FilePath(DRIVE FPL("/test/system/isolated"))));
+      base::FilePath(DRIVE FPL("/test/system/isolated"))));
   // Add a mount points with the same name as a system mount point to
   // FileSystemContext's external mount points.
   ASSERT_TRUE(external_mount_points->RegisterFileSystem(
       "ext",
        kFileSystemTypeNativeLocal,
-       FilePath(DRIVE FPL("/test/local/ext/"))));
+       base::FilePath(DRIVE FPL("/test/local/ext/"))));
 
   const GURL kTestOrigin = GURL("http://chromium.org/");
-  const FilePath kVirtualPathNoRoot = FilePath(FPL("root/file"));
+  const base::FilePath kVirtualPathNoRoot = base::FilePath(FPL("root/file"));
 
   struct TestCase {
     // Test case values.
@@ -225,7 +225,7 @@ TEST_F(FileSystemContextTest, CrackFileSystemURL) {
     bool expect_is_valid;
     FileSystemType expect_mount_type;
     FileSystemType expect_type;
-    const FilePath::CharType* expect_path;
+    const base::FilePath::CharType* expect_path;
     bool expect_virtual_path_empty;
     std::string expect_filesystem_id;
   };
@@ -290,8 +290,8 @@ TEST_F(FileSystemContextTest, CrackFileSystemURL) {
   };
 
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kTestCases); ++i) {
-    const FilePath virtual_path =
-        FilePath::FromUTF8Unsafe(kTestCases[i].root).Append(kVirtualPathNoRoot);
+    const base::FilePath virtual_path =
+        base::FilePath::FromUTF8Unsafe(kTestCases[i].root).Append(kVirtualPathNoRoot);
 
     GURL raw_url =
         CreateRawFileSystemURL(kTestCases[i].type_str, kTestCases[i].root);
@@ -309,14 +309,14 @@ TEST_F(FileSystemContextTest, CrackFileSystemURL) {
         GURL(kTestOrigin),
         kTestCases[i].expect_mount_type,
         kTestCases[i].expect_type,
-        FilePath(kTestCases[i].expect_path).NormalizePathSeparators(),
+        base::FilePath(kTestCases[i].expect_path).NormalizePathSeparators(),
         kTestCases[i].expect_virtual_path_empty ?
-            FilePath() : virtual_path.NormalizePathSeparators(),
+            base::FilePath() : virtual_path.NormalizePathSeparators(),
         kTestCases[i].expect_filesystem_id);
   }
 
   IsolatedContext::GetInstance()->RevokeFileSystemByPath(
-      FilePath(DRIVE FPL("/test/isolated/root")));
+      base::FilePath(DRIVE FPL("/test/isolated/root")));
   ExternalMountPoints::GetSystemInstance()->RevokeFileSystem("system");
   ExternalMountPoints::GetSystemInstance()->RevokeFileSystem("ext");
   ExternalMountPoints::GetSystemInstance()->RevokeFileSystem(
diff --git a/webkit/fileapi/file_system_database_test_helper.cc b/webkit/fileapi/file_system_database_test_helper.cc
index 838173a8916307..da1a5e13a28135 100644
--- a/webkit/fileapi/file_system_database_test_helper.cc
+++ b/webkit/fileapi/file_system_database_test_helper.cc
@@ -15,15 +15,15 @@
 
 namespace fileapi {
 
-void CorruptDatabase(const FilePath& db_path,
+void CorruptDatabase(const base::FilePath& db_path,
                      leveldb::FileType type,
                      ptrdiff_t offset,
                      size_t size) {
   file_util::FileEnumerator file_enum(db_path, false /* not recursive */,
       file_util::FileEnumerator::DIRECTORIES |
       file_util::FileEnumerator::FILES);
-  FilePath file_path;
-  FilePath picked_file_path;
+  base::FilePath file_path;
+  base::FilePath picked_file_path;
   uint64 picked_file_number = kuint64max;
 
   while (!(file_path = file_enum.Next()).empty()) {
diff --git a/webkit/fileapi/file_system_database_test_helper.h b/webkit/fileapi/file_system_database_test_helper.h
index 87e35e07fb6959..67689c131076b5 100644
--- a/webkit/fileapi/file_system_database_test_helper.h
+++ b/webkit/fileapi/file_system_database_test_helper.h
@@ -9,11 +9,13 @@
 
 #include "third_party/leveldatabase/src/db/filename.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace fileapi {
 
-void CorruptDatabase(const FilePath& db_path,
+void CorruptDatabase(const base::FilePath& db_path,
                      leveldb::FileType type,
                      ptrdiff_t offset,
                      size_t size);
diff --git a/webkit/fileapi/file_system_dir_url_request_job.cc b/webkit/fileapi/file_system_dir_url_request_job.cc
index e1031dfe9b4d57..5943bcd6bd8ead 100644
--- a/webkit/fileapi/file_system_dir_url_request_job.cc
+++ b/webkit/fileapi/file_system_dir_url_request_job.cc
@@ -108,9 +108,9 @@ void FileSystemDirURLRequestJob::DidReadDirectory(
     return;
 
   if (data_.empty()) {
-    FilePath relative_path = url_.path();
+    base::FilePath relative_path = url_.path();
 #if defined(OS_POSIX)
-    relative_path = FilePath(FILE_PATH_LITERAL("/") + relative_path.value());
+    relative_path = base::FilePath(FILE_PATH_LITERAL("/") + relative_path.value());
 #endif
     const string16& title = relative_path.LossyDisplayName();
     data_.append(net::GetDirectoryListingHeader(title));
@@ -118,7 +118,7 @@ void FileSystemDirURLRequestJob::DidReadDirectory(
 
   typedef std::vector<base::FileUtilProxy::Entry>::const_iterator EntryIterator;
   for (EntryIterator it = entries.begin(); it != entries.end(); ++it) {
-    const string16& name = FilePath(it->name).LossyDisplayName();
+    const string16& name = base::FilePath(it->name).LossyDisplayName();
     data_.append(net::GetDirectoryListingEntry(
         name, std::string(), it->is_directory, it->size,
         it->last_modified_time));
diff --git a/webkit/fileapi/file_system_dir_url_request_job_unittest.cc b/webkit/fileapi/file_system_dir_url_request_job_unittest.cc
index 0af56c484f9d66..b825c61cb71468 100644
--- a/webkit/fileapi/file_system_dir_url_request_job_unittest.cc
+++ b/webkit/fileapi/file_system_dir_url_request_job_unittest.cc
@@ -106,7 +106,7 @@ class FileSystemDirURLRequestJobTest : public testing::Test {
     TestRequestHelper(url, false);
   }
 
-  FileSystemURL CreateURL(const FilePath& file_path) {
+  FileSystemURL CreateURL(const base::FilePath& file_path) {
     return file_system_context_->CreateCrackedFileSystemURL(
         GURL("http://remote"),
         fileapi::kFileSystemTypeTemporary,
@@ -121,7 +121,7 @@ class FileSystemDirURLRequestJobTest : public testing::Test {
   }
 
   void CreateDirectory(const base::StringPiece& dir_name) {
-    FilePath path = FilePath().AppendASCII(dir_name);
+    base::FilePath path = base::FilePath().AppendASCII(dir_name);
     scoped_ptr<FileSystemOperationContext> context(NewOperationContext());
     ASSERT_EQ(base::PLATFORM_FILE_OK, file_util()->CreateDirectory(
         context.get(),
@@ -131,22 +131,22 @@ class FileSystemDirURLRequestJobTest : public testing::Test {
   }
 
   void EnsureFileExists(const base::StringPiece file_name) {
-    FilePath path = FilePath().AppendASCII(file_name);
+    base::FilePath path = base::FilePath().AppendASCII(file_name);
     scoped_ptr<FileSystemOperationContext> context(NewOperationContext());
     ASSERT_EQ(base::PLATFORM_FILE_OK, file_util()->EnsureFileExists(
         context.get(), CreateURL(path), NULL));
   }
 
   void TruncateFile(const base::StringPiece file_name, int64 length) {
-    FilePath path = FilePath().AppendASCII(file_name);
+    base::FilePath path = base::FilePath().AppendASCII(file_name);
     scoped_ptr<FileSystemOperationContext> context(NewOperationContext());
     ASSERT_EQ(base::PLATFORM_FILE_OK, file_util()->Truncate(
         context.get(), CreateURL(path), length));
   }
 
-  base::PlatformFileError GetFileInfo(const FilePath& path,
+  base::PlatformFileError GetFileInfo(const base::FilePath& path,
                                       base::PlatformFileInfo* file_info,
-                                      FilePath* platform_file_path) {
+                                      base::FilePath* platform_file_path) {
     scoped_ptr<FileSystemOperationContext> context(NewOperationContext());
     return file_util()->GetFileInfo(context.get(),
                                     CreateURL(path),
diff --git a/webkit/fileapi/file_system_directory_database.cc b/webkit/fileapi/file_system_directory_database.cc
index 6dea0634eaa712..900ef57b40a7c5 100644
--- a/webkit/fileapi/file_system_directory_database.cc
+++ b/webkit/fileapi/file_system_directory_database.cc
@@ -33,7 +33,7 @@ bool PickleFromFileInfo(
   std::string name;
 
   data_path = fileapi::FilePathToString(info.data_path);
-  name = fileapi::FilePathToString(FilePath(info.name));
+  name = fileapi::FilePathToString(base::FilePath(info.name));
 
   if (pickle->WriteInt64(info.parent_id) &&
       pickle->WriteString(data_path) &&
@@ -66,7 +66,7 @@ bool FileInfoFromPickle(
   return false;
 }
 
-const FilePath::CharType kDirectoryDatabaseName[] = FILE_PATH_LITERAL("Paths");
+const base::FilePath::CharType kDirectoryDatabaseName[] = FILE_PATH_LITERAL("Paths");
 const char kChildLookupPrefix[] = "CHILD_OF:";
 const char kChildLookupSeparator[] = ":";
 const char kLastFileIdKey[] = "LAST_FILE_ID";
@@ -84,9 +84,9 @@ enum InitStatus {
 
 std::string GetChildLookupKey(
     fileapi::FileSystemDirectoryDatabase::FileId parent_id,
-    const FilePath::StringType& child_name) {
+    const base::FilePath::StringType& child_name) {
   std::string name;
-  name = fileapi::FilePathToString(FilePath(child_name));
+  name = fileapi::FilePathToString(base::FilePath(child_name));
   return std::string(kChildLookupPrefix) + base::Int64ToString(parent_id) +
       std::string(kChildLookupSeparator) + name;
 }
@@ -129,7 +129,7 @@ class DatabaseCheckHelper {
 
   DatabaseCheckHelper(fileapi::FileSystemDirectoryDatabase* dir_db,
                       leveldb::DB* db,
-                      const FilePath& path);
+                      const base::FilePath& path);
 
   bool IsFileSystemConsistent() {
     return IsDatabaseEmpty() ||
@@ -147,9 +147,9 @@ class DatabaseCheckHelper {
 
   fileapi::FileSystemDirectoryDatabase* dir_db_;
   leveldb::DB* db_;
-  FilePath path_;
+  base::FilePath path_;
 
-  std::set<FilePath> files_in_db_;
+  std::set<base::FilePath> files_in_db_;
 
   size_t num_directories_in_db_;
   size_t num_files_in_db_;
@@ -162,7 +162,7 @@ class DatabaseCheckHelper {
 DatabaseCheckHelper::DatabaseCheckHelper(
     fileapi::FileSystemDirectoryDatabase* dir_db,
     leveldb::DB* db,
-    const FilePath& path)
+    const base::FilePath& path)
     : dir_db_(dir_db), db_(db), path_(path),
       num_directories_in_db_(0),
       num_files_in_db_(0),
@@ -260,17 +260,17 @@ bool DatabaseCheckHelper::ScanDatabase() {
 bool DatabaseCheckHelper::ScanDirectory() {
   // TODO(kinuko): Scans all local file system entries to verify each of them
   // has a database entry.
-  const FilePath kExcludes[] = {
-    FilePath(kDirectoryDatabaseName),
-    FilePath(fileapi::FileSystemUsageCache::kUsageFileName),
+  const base::FilePath kExcludes[] = {
+    base::FilePath(kDirectoryDatabaseName),
+    base::FilePath(fileapi::FileSystemUsageCache::kUsageFileName),
   };
 
   // Any path in |pending_directories| is relative to |path_|.
-  std::stack<FilePath> pending_directories;
-  pending_directories.push(FilePath());
+  std::stack<base::FilePath> pending_directories;
+  pending_directories.push(base::FilePath());
 
   while (!pending_directories.empty()) {
-    FilePath dir_path = pending_directories.top();
+    base::FilePath dir_path = pending_directories.top();
     pending_directories.pop();
 
     file_util::FileEnumerator file_enum(
@@ -279,12 +279,12 @@ bool DatabaseCheckHelper::ScanDirectory() {
         file_util::FileEnumerator::DIRECTORIES |
         file_util::FileEnumerator::FILES);
 
-    FilePath absolute_file_path;
+    base::FilePath absolute_file_path;
     while (!(absolute_file_path = file_enum.Next()).empty()) {
       file_util::FileEnumerator::FindInfo find_info;
       file_enum.GetFindInfo(&find_info);
 
-      FilePath relative_file_path;
+      base::FilePath relative_file_path;
       if (!path_.AppendRelativePath(absolute_file_path, &relative_file_path))
         return false;
 
@@ -298,7 +298,7 @@ bool DatabaseCheckHelper::ScanDirectory() {
       }
 
       // Check if the file has a database entry.
-      std::set<FilePath>::iterator itr = files_in_db_.find(relative_file_path);
+      std::set<base::FilePath>::iterator itr = files_in_db_.find(relative_file_path);
       if (itr == files_in_db_.end()) {
         if (!file_util::Delete(absolute_file_path, false))
           return false;
@@ -373,15 +373,15 @@ bool DatabaseCheckHelper::ScanHierarchy() {
 // and does not refer to special system files.
 // This is called in GetFileInfo, AddFileInfo and UpdateFileInfo to
 // ensure we're only dealing with valid data paths.
-bool VerifyDataPath(const FilePath& data_path) {
+bool VerifyDataPath(const base::FilePath& data_path) {
   // |data_path| should not contain any ".." and should be a relative path
   // (to the filesystem_data_directory_).
   if (data_path.ReferencesParent() || data_path.IsAbsolute())
     return false;
   // See if it's not pointing to the special system paths.
-  const FilePath kExcludes[] = {
-    FilePath(kDirectoryDatabaseName),
-    FilePath(fileapi::FileSystemUsageCache::kUsageFileName),
+  const base::FilePath kExcludes[] = {
+    base::FilePath(kDirectoryDatabaseName),
+    base::FilePath(fileapi::FileSystemUsageCache::kUsageFileName),
   };
   for (size_t i = 0; i < arraysize(kExcludes); ++i) {
     if (data_path == kExcludes[i] || kExcludes[i].IsParent(data_path))
@@ -401,7 +401,7 @@ FileSystemDirectoryDatabase::FileInfo::~FileInfo() {
 }
 
 FileSystemDirectoryDatabase::FileSystemDirectoryDatabase(
-    const FilePath& filesystem_data_directory)
+    const base::FilePath& filesystem_data_directory)
     : filesystem_data_directory_(filesystem_data_directory) {
 }
 
@@ -409,7 +409,7 @@ FileSystemDirectoryDatabase::~FileSystemDirectoryDatabase() {
 }
 
 bool FileSystemDirectoryDatabase::GetChildWithName(
-    FileId parent_id, const FilePath::StringType& name, FileId* child_id) {
+    FileId parent_id, const base::FilePath::StringType& name, FileId* child_id) {
   if (!Init(REPAIR_ON_CORRUPTION))
     return false;
   DCHECK(child_id);
@@ -431,13 +431,13 @@ bool FileSystemDirectoryDatabase::GetChildWithName(
 }
 
 bool FileSystemDirectoryDatabase::GetFileWithPath(
-    const FilePath& path, FileId* file_id) {
-  std::vector<FilePath::StringType> components;
+    const base::FilePath& path, FileId* file_id) {
+  std::vector<base::FilePath::StringType> components;
   VirtualPath::GetComponents(path, &components);
   FileId local_id = 0;
-  std::vector<FilePath::StringType>::iterator iter;
+  std::vector<base::FilePath::StringType>::iterator iter;
   for (iter = components.begin(); iter != components.end(); ++iter) {
-    FilePath::StringType name;
+    base::FilePath::StringType name;
     name = *iter;
     if (name == FILE_PATH_LITERAL("/"))
       continue;
@@ -497,8 +497,8 @@ bool FileSystemDirectoryDatabase::GetFileInfo(FileId file_id, FileInfo* info) {
   // Without this, a query for the root's file info, made before creating the
   // first file in the database, will fail and confuse callers.
   if (status.IsNotFound() && !file_id) {
-    info->name = FilePath::StringType();
-    info->data_path = FilePath();
+    info->name = base::FilePath::StringType();
+    info->data_path = base::FilePath();
     info->modification_time = base::Time::Now();
     info->parent_id = 0;
     return true;
@@ -686,7 +686,7 @@ bool FileSystemDirectoryDatabase::GetNextInteger(int64* next) {
 }
 
 // static
-bool FileSystemDirectoryDatabase::DestroyDatabase(const FilePath& path) {
+bool FileSystemDirectoryDatabase::DestroyDatabase(const base::FilePath& path) {
   std::string name  = FilePathToString(path.Append(kDirectoryDatabaseName));
   leveldb::Status status = leveldb::DestroyDB(name, leveldb::Options());
   if (status.ok())
diff --git a/webkit/fileapi/file_system_directory_database.h b/webkit/fileapi/file_system_directory_database.h
index c411f497c5c515..5ab9ec11a88773 100644
--- a/webkit/fileapi/file_system_directory_database.h
+++ b/webkit/fileapi/file_system_directory_database.h
@@ -47,8 +47,8 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemDirectoryDatabase {
     }
 
     FileId parent_id;
-    FilePath data_path;
-    FilePath::StringType name;
+    base::FilePath data_path;
+    base::FilePath::StringType name;
     // This modification time is valid only for directories, not files, as
     // FileWriter will get the files out of sync.
     // For files, look at the modification time of the underlying data_path.
@@ -56,12 +56,12 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemDirectoryDatabase {
   };
 
   explicit FileSystemDirectoryDatabase(
-      const FilePath& filesystem_data_directory);
+      const base::FilePath& filesystem_data_directory);
   ~FileSystemDirectoryDatabase();
 
   bool GetChildWithName(
-      FileId parent_id, const FilePath::StringType& name, FileId* child_id);
-  bool GetFileWithPath(const FilePath& path, FileId* file_id);
+      FileId parent_id, const base::FilePath::StringType& name, FileId* child_id);
+  bool GetFileWithPath(const base::FilePath& path, FileId* file_id);
   // ListChildren will succeed, returning 0 children, if parent_id doesn't
   // exist.
   bool ListChildren(FileId parent_id, std::vector<FileId>* children);
@@ -88,7 +88,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemDirectoryDatabase {
   // Returns true if the database looks consistent with local filesystem.
   bool IsFileSystemConsistent();
 
-  static bool DestroyDatabase(const FilePath& path);
+  static bool DestroyDatabase(const base::FilePath& path);
 
  private:
   enum RecoveryOption {
@@ -111,7 +111,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemDirectoryDatabase {
   void HandleError(const tracked_objects::Location& from_here,
                    const leveldb::Status& status);
 
-  const FilePath filesystem_data_directory_;
+  const base::FilePath filesystem_data_directory_;
   scoped_ptr<leveldb::DB> db_;
   base::Time last_reported_time_;
   DISALLOW_COPY_AND_ASSIGN(FileSystemDirectoryDatabase);
diff --git a/webkit/fileapi/file_system_directory_database_unittest.cc b/webkit/fileapi/file_system_directory_database_unittest.cc
index d5c31ae3bc920a..3f15e7e3438e4f 100644
--- a/webkit/fileapi/file_system_directory_database_unittest.cc
+++ b/webkit/fileapi/file_system_directory_database_unittest.cc
@@ -23,7 +23,7 @@
 namespace fileapi {
 
 namespace {
-const FilePath::CharType kDirectoryDatabaseName[] = FPL("Paths");
+const base::FilePath::CharType kDirectoryDatabaseName[] = FPL("Paths");
 }
 
 class FileSystemDirectoryDatabaseTest : public testing::Test {
@@ -51,7 +51,7 @@ class FileSystemDirectoryDatabaseTest : public testing::Test {
     db_.reset();
   }
 
-  bool AddFileInfo(FileId parent_id, const FilePath::StringType& name) {
+  bool AddFileInfo(FileId parent_id, const base::FilePath::StringType& name) {
     FileId file_id;
     FileInfo info;
     info.parent_id = parent_id;
@@ -60,7 +60,7 @@ class FileSystemDirectoryDatabaseTest : public testing::Test {
   }
 
   void CreateDirectory(FileId parent_id,
-                       const FilePath::StringType& name,
+                       const base::FilePath::StringType& name,
                        FileId* file_id_out) {
     FileInfo info;
     info.parent_id = parent_id;
@@ -69,18 +69,18 @@ class FileSystemDirectoryDatabaseTest : public testing::Test {
   }
 
   void CreateFile(FileId parent_id,
-                  const FilePath::StringType& name,
-                  const FilePath::StringType& data_path,
+                  const base::FilePath::StringType& name,
+                  const base::FilePath::StringType& data_path,
                   FileId* file_id_out) {
     FileId file_id;
 
     FileInfo info;
     info.parent_id = parent_id;
     info.name = name;
-    info.data_path = FilePath(data_path).NormalizePathSeparators();
+    info.data_path = base::FilePath(data_path).NormalizePathSeparators();
     ASSERT_TRUE(db_->AddFileInfo(info, &file_id));
 
-    FilePath local_path = path().Append(data_path);
+    base::FilePath local_path = path().Append(data_path);
     if (!file_util::DirectoryExists(local_path.DirName()))
       ASSERT_TRUE(file_util::CreateDirectory(local_path.DirName()));
 
@@ -110,18 +110,18 @@ class FileSystemDirectoryDatabaseTest : public testing::Test {
         FilePathToString(path().Append(kDirectoryDatabaseName)));
   }
 
-  const FilePath& path() {
+  const base::FilePath& path() {
     return base_.path();
   }
 
   // Makes link from |parent_id| to |child_id| with |name|.
   void MakeHierarchyLink(FileId parent_id,
                          FileId child_id,
-                         const FilePath::StringType& name) {
+                         const base::FilePath::StringType& name) {
     ASSERT_TRUE(db()->db_->Put(
         leveldb::WriteOptions(),
         "CHILD_OF:" + base::Int64ToString(parent_id) + ":" +
-        FilePathToString(FilePath(name)),
+        FilePathToString(base::FilePath(name)),
         base::Int64ToString(child_id)).ok());
   }
 
@@ -132,7 +132,7 @@ class FileSystemDirectoryDatabaseTest : public testing::Test {
     ASSERT_TRUE(db()->db_->Delete(
         leveldb::WriteOptions(),
         "CHILD_OF:" + base::Int64ToString(file_info.parent_id) + ":" +
-        FilePathToString(FilePath(file_info.name))).ok());
+        FilePathToString(base::FilePath(file_info.name))).ok());
   }
 
  protected:
@@ -171,7 +171,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestAddNameClash) {
   EXPECT_TRUE(db()->AddFileInfo(info, &file_id));
 
   // Check for name clash in the root directory.
-  FilePath::StringType name = info.name;
+  base::FilePath::StringType name = info.name;
   EXPECT_FALSE(AddFileInfo(0, name));
   name = FILE_PATH_LITERAL("dir 1");
   EXPECT_TRUE(AddFileInfo(0, name));
@@ -188,9 +188,9 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestAddNameClash) {
 TEST_F(FileSystemDirectoryDatabaseTest, TestRenameNoMoveNameClash) {
   FileInfo info;
   FileId file_id0;
-  FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
-  FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
-  FilePath::StringType name2 = FILE_PATH_LITERAL("bas");
+  base::FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
+  base::FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
+  base::FilePath::StringType name2 = FILE_PATH_LITERAL("bas");
   info.parent_id = 0;
   info.name = name0;
   EXPECT_TRUE(db()->AddFileInfo(info, &file_id0));
@@ -205,8 +205,8 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestMoveSameNameNameClash) {
   FileInfo info;
   FileId file_id0;
   FileId file_id1;
-  FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
-  FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
+  base::FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
+  base::FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
   info.parent_id = 0;
   info.name = name0;
   EXPECT_TRUE(db()->AddFileInfo(info, &file_id0));
@@ -222,9 +222,9 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestMoveRenameNameClash) {
   FileInfo info;
   FileId file_id0;
   FileId file_id1;
-  FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
-  FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
-  FilePath::StringType name2 = FILE_PATH_LITERAL("bas");
+  base::FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
+  base::FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
+  base::FilePath::StringType name2 = FILE_PATH_LITERAL("bas");
   info.parent_id = 0;
   info.name = name0;
   EXPECT_TRUE(db()->AddFileInfo(info, &file_id0));
@@ -260,8 +260,8 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestGetChildWithName) {
   FileInfo info;
   FileId file_id0;
   FileId file_id1;
-  FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
-  FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
+  base::FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
+  base::FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
   info.parent_id = 0;
   info.name = name0;
   EXPECT_TRUE(db()->AddFileInfo(info, &file_id0));
@@ -284,9 +284,9 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestGetFileWithPath) {
   FileId file_id0;
   FileId file_id1;
   FileId file_id2;
-  FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
-  FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
-  FilePath::StringType name2 = FILE_PATH_LITERAL("dog");
+  base::FilePath::StringType name0 = FILE_PATH_LITERAL("foo");
+  base::FilePath::StringType name1 = FILE_PATH_LITERAL("bar");
+  base::FilePath::StringType name2 = FILE_PATH_LITERAL("dog");
 
   info.parent_id = 0;
   info.name = name0;
@@ -302,7 +302,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestGetFileWithPath) {
   EXPECT_NE(file_id1, file_id2);
 
   FileId check_file_id;
-  FilePath path = FilePath(name0);
+  base::FilePath path = base::FilePath(name0);
   EXPECT_TRUE(db()->GetFileWithPath(path, &check_file_id));
   EXPECT_EQ(file_id0, check_file_id);
 
@@ -376,7 +376,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestUpdateModificationTime) {
   FileId file_id;
   info0.parent_id = 0;
   info0.name = FILE_PATH_LITERAL("name");
-  info0.data_path = FilePath(FILE_PATH_LITERAL("fake path"));
+  info0.data_path = base::FilePath(FILE_PATH_LITERAL("fake path"));
   info0.modification_time = base::Time::Now();
   EXPECT_TRUE(db()->AddFileInfo(info0, &file_id));
   FileInfo info1;
@@ -406,7 +406,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestSimpleFileOperations) {
   FileInfo info0;
   EXPECT_FALSE(db()->GetFileInfo(file_id, &info0));
   info0.parent_id = 0;
-  info0.data_path = FilePath(FILE_PATH_LITERAL("foo"));
+  info0.data_path = base::FilePath(FILE_PATH_LITERAL("foo"));
   info0.name = FILE_PATH_LITERAL("file name");
   info0.modification_time = base::Time::Now();
   EXPECT_TRUE(db()->AddFileInfo(info0, &file_id));
@@ -431,7 +431,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestOverwritingMoveFileSrcDirectory) {
   FileId file_id;
   FileInfo info1;
   info1.parent_id = 0;
-  info1.data_path = FilePath(FILE_PATH_LITERAL("bar"));
+  info1.data_path = base::FilePath(FILE_PATH_LITERAL("bar"));
   info1.name = FILE_PATH_LITERAL("file");
   info1.modification_time = base::Time::UnixEpoch();
   EXPECT_TRUE(db()->AddFileInfo(info1, &file_id));
@@ -444,7 +444,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestOverwritingMoveFileDestDirectory) {
   FileInfo info0;
   info0.parent_id = 0;
   info0.name = FILE_PATH_LITERAL("file");
-  info0.data_path = FilePath(FILE_PATH_LITERAL("bar"));
+  info0.data_path = base::FilePath(FILE_PATH_LITERAL("bar"));
   info0.modification_time = base::Time::Now();
   EXPECT_TRUE(db()->AddFileInfo(info0, &file_id));
 
@@ -462,7 +462,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestOverwritingMoveFileSuccess) {
   FileId file_id0;
   FileInfo info0;
   info0.parent_id = 0;
-  info0.data_path = FilePath(FILE_PATH_LITERAL("foo"));
+  info0.data_path = base::FilePath(FILE_PATH_LITERAL("foo"));
   info0.name = FILE_PATH_LITERAL("file name 0");
   info0.modification_time = base::Time::Now();
   EXPECT_TRUE(db()->AddFileInfo(info0, &file_id0));
@@ -476,7 +476,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestOverwritingMoveFileSuccess) {
   FileId file_id1;
   FileInfo info1;
   info1.parent_id = dir_id;
-  info1.data_path = FilePath(FILE_PATH_LITERAL("bar"));
+  info1.data_path = base::FilePath(FILE_PATH_LITERAL("bar"));
   info1.name = FILE_PATH_LITERAL("file name 1");
   info1.modification_time = base::Time::UnixEpoch();
   EXPECT_TRUE(db()->AddFileInfo(info1, &file_id1));
@@ -486,9 +486,9 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestOverwritingMoveFileSuccess) {
   FileInfo check_info;
   FileId check_id;
 
-  EXPECT_FALSE(db()->GetFileWithPath(FilePath(info0.name), &check_id));
+  EXPECT_FALSE(db()->GetFileWithPath(base::FilePath(info0.name), &check_id));
   EXPECT_TRUE(db()->GetFileWithPath(
-      FilePath(dir_info.name).Append(info1.name), &check_id));
+      base::FilePath(dir_info.name).Append(info1.name), &check_id));
   EXPECT_TRUE(db()->GetFileInfo(check_id, &check_info));
 
   EXPECT_EQ(info0.data_path, check_info.data_path);
@@ -531,7 +531,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestConsistencyCheck_Consistent) {
 
 TEST_F(FileSystemDirectoryDatabaseTest,
        TestConsistencyCheck_BackingMultiEntry) {
-  const FilePath::CharType kBackingFileName[] = FPL("the celeb");
+  const base::FilePath::CharType kBackingFileName[] = FPL("the celeb");
   CreateFile(0, FPL("foo"), kBackingFileName, NULL);
 
   EXPECT_TRUE(db()->IsFileSystemConsistent());
@@ -541,7 +541,7 @@ TEST_F(FileSystemDirectoryDatabaseTest,
 }
 
 TEST_F(FileSystemDirectoryDatabaseTest, TestConsistencyCheck_FileLost) {
-  const FilePath::CharType kBackingFileName[] = FPL("hoge");
+  const base::FilePath::CharType kBackingFileName[] = FPL("hoge");
   CreateFile(0, FPL("foo"), kBackingFileName, NULL);
 
   EXPECT_TRUE(db()->IsFileSystemConsistent());
@@ -576,7 +576,7 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestConsistencyCheck_RootLoop) {
 TEST_F(FileSystemDirectoryDatabaseTest, TestConsistencyCheck_DirectoryLoop) {
   FileId dir1_id;
   FileId dir2_id;
-  FilePath::StringType dir1_name = FPL("foo");
+  base::FilePath::StringType dir1_name = FPL("foo");
   CreateDirectory(0, dir1_name, &dir1_id);
   CreateDirectory(dir1_id, FPL("bar"), &dir2_id);
 
@@ -610,13 +610,13 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestConsistencyCheck_WreckedEntries) {
 }
 
 TEST_F(FileSystemDirectoryDatabaseTest, TestRepairDatabase_Success) {
-  FilePath::StringType kFileName = FPL("bar");
+  base::FilePath::StringType kFileName = FPL("bar");
 
   FileId file_id_prev;
   CreateFile(0, FPL("foo"), FPL("hoge"), NULL);
   CreateFile(0, kFileName, FPL("fuga"), &file_id_prev);
 
-  const FilePath kDatabaseDirectory = path().Append(kDirectoryDatabaseName);
+  const base::FilePath kDatabaseDirectory = path().Append(kDirectoryDatabaseName);
   CloseDatabase();
   CorruptDatabase(kDatabaseDirectory, leveldb::kDescriptorFile,
                   0, std::numeric_limits<size_t>::max());
@@ -631,12 +631,12 @@ TEST_F(FileSystemDirectoryDatabaseTest, TestRepairDatabase_Success) {
 }
 
 TEST_F(FileSystemDirectoryDatabaseTest, TestRepairDatabase_Failure) {
-  FilePath::StringType kFileName = FPL("bar");
+  base::FilePath::StringType kFileName = FPL("bar");
 
   CreateFile(0, FPL("foo"), FPL("hoge"), NULL);
   CreateFile(0, kFileName, FPL("fuga"), NULL);
 
-  const FilePath kDatabaseDirectory = path().Append(kDirectoryDatabaseName);
+  const base::FilePath kDatabaseDirectory = path().Append(kDirectoryDatabaseName);
   CloseDatabase();
   CorruptDatabase(kDatabaseDirectory, leveldb::kDescriptorFile,
                   0, std::numeric_limits<size_t>::max());
diff --git a/webkit/fileapi/file_system_file_stream_reader.cc b/webkit/fileapi/file_system_file_stream_reader.cc
index cb5f5dd8434226..e5e029963b088b 100644
--- a/webkit/fileapi/file_system_file_stream_reader.cc
+++ b/webkit/fileapi/file_system_file_stream_reader.cc
@@ -107,7 +107,7 @@ void FileSystemFileStreamReader::DidCreateSnapshot(
     const net::CompletionCallback& error_callback,
     base::PlatformFileError file_error,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path,
+    const base::FilePath& platform_path,
     const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref) {
   DCHECK(has_pending_create_snapshot_);
   DCHECK(!local_file_reader_.get());
diff --git a/webkit/fileapi/file_system_file_stream_reader.h b/webkit/fileapi/file_system_file_stream_reader.h
index 5115f722411f6a..0a6e750af82110 100644
--- a/webkit/fileapi/file_system_file_stream_reader.h
+++ b/webkit/fileapi/file_system_file_stream_reader.h
@@ -14,9 +14,8 @@
 #include "webkit/fileapi/file_system_url.h"
 #include "webkit/storage/webkit_storage_export.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 }
 
@@ -60,7 +59,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemFileStreamReader
       const net::CompletionCallback& error_callback,
       base::PlatformFileError file_error,
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
 
   scoped_refptr<FileSystemContext> file_system_context_;
diff --git a/webkit/fileapi/file_system_file_stream_reader_unittest.cc b/webkit/fileapi/file_system_file_stream_reader_unittest.cc
index 55d0b9fd1e08ae..327cb64a13da69 100644
--- a/webkit/fileapi/file_system_file_stream_reader_unittest.cc
+++ b/webkit/fileapi/file_system_file_stream_reader_unittest.cc
@@ -133,7 +133,7 @@ class FileSystemFileStreamReaderTest : public testing::Test {
     base::ClosePlatformFile(handle);
 
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util->GetFileInfo(&context, url, &file_info,
                                      &platform_path));
@@ -150,7 +150,7 @@ class FileSystemFileStreamReaderTest : public testing::Test {
     return file_system_context_->CreateCrackedFileSystemURL(
         GURL(kURLOrigin),
         kFileSystemTypeTemporary,
-        FilePath().AppendASCII(file_name));
+        base::FilePath().AppendASCII(file_name));
   }
 
   MessageLoop message_loop_;
diff --git a/webkit/fileapi/file_system_file_util.cc b/webkit/fileapi/file_system_file_util.cc
index 46b8b02dde22c8..9d786ef238b829 100644
--- a/webkit/fileapi/file_system_file_util.cc
+++ b/webkit/fileapi/file_system_file_util.cc
@@ -6,8 +6,8 @@
 
 namespace fileapi {
 
-FilePath FileSystemFileUtil::EmptyFileEnumerator::Next() {
-  return FilePath();
+base::FilePath FileSystemFileUtil::EmptyFileEnumerator::Next() {
+  return base::FilePath();
 }
 
 int64 FileSystemFileUtil::EmptyFileEnumerator::Size() {
diff --git a/webkit/fileapi/file_system_file_util.h b/webkit/fileapi/file_system_file_util.h
index 5d4b72cf4ad371..e4e94bec488f78 100644
--- a/webkit/fileapi/file_system_file_util.h
+++ b/webkit/fileapi/file_system_file_util.h
@@ -33,7 +33,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
     virtual ~AbstractFileEnumerator() {}
 
     // Returns an empty string if there are no more results.
-    virtual FilePath Next() = 0;
+    virtual base::FilePath Next() = 0;
 
     // These methods return metadata for the file most recently returned by
     // Next(). If Next() has never been called, or if Next() most recently
@@ -46,7 +46,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
 
   class WEBKIT_STORAGE_EXPORT EmptyFileEnumerator
       : public AbstractFileEnumerator {
-    virtual FilePath Next() OVERRIDE;
+    virtual base::FilePath Next() OVERRIDE;
     virtual int64 Size() OVERRIDE;
     virtual base::Time LastModifiedTime() OVERRIDE;
     virtual bool IsDirectory() OVERRIDE;
@@ -91,7 +91,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path) = 0;
+      base::FilePath* platform_path) = 0;
 
   // Returns a pointer to a new instance of AbstractFileEnumerator which is
   // implemented for each FileSystemFileUtil subclass. The instance needs to be
@@ -114,7 +114,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
   virtual base::PlatformFileError GetLocalFilePath(
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
-      FilePath* local_file_path) = 0;
+      base::FilePath* local_file_path) = 0;
 
   // Updates the file metadata information.
   // See header comments for AsyncFileUtil::Touch() for more details.
@@ -154,7 +154,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
   // more details.
   virtual base::PlatformFileError CopyInForeignFile(
         FileSystemOperationContext* context,
-        const FilePath& src_file_path,
+        const base::FilePath& src_file_path,
         const FileSystemURL& dest_url) = 0;
 
   // Deletes a single file.
@@ -178,7 +178,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path,
+      base::FilePath* platform_path,
       SnapshotFilePolicy* policy) = 0;
 
  protected:
diff --git a/webkit/fileapi/file_system_file_util_proxy.cc b/webkit/fileapi/file_system_file_util_proxy.cc
index 35c08bf9c0fb06..8ab1c4fe721ae3 100644
--- a/webkit/fileapi/file_system_file_util_proxy.cc
+++ b/webkit/fileapi/file_system_file_util_proxy.cc
@@ -79,7 +79,7 @@ class GetFileInfoHelper {
  private:
   base::PlatformFileError error_;
   base::PlatformFileInfo file_info_;
-  FilePath platform_path_;
+  base::FilePath platform_path_;
   FileSystemFileUtil::SnapshotFilePolicy snapshot_policy_;
   DISALLOW_COPY_AND_ASSIGN(GetFileInfoHelper);
 };
@@ -181,7 +181,7 @@ bool FileSystemFileUtilProxy::MoveFileLocal(
 bool FileSystemFileUtilProxy::CopyInForeignFile(
     FileSystemOperationContext* context,
     FileSystemFileUtil* file_util,
-    const FilePath& src_local_disk_file_path,
+    const base::FilePath& src_local_disk_file_path,
     const FileSystemURL& dest_url,
     const StatusCallback& callback) {
   return base::PostTaskAndReplyWithResult(
diff --git a/webkit/fileapi/file_system_file_util_proxy.h b/webkit/fileapi/file_system_file_util_proxy.h
index 3c43e30bc43edf..c20b8b558f32e8 100644
--- a/webkit/fileapi/file_system_file_util_proxy.h
+++ b/webkit/fileapi/file_system_file_util_proxy.h
@@ -37,7 +37,7 @@ class FileSystemFileUtilProxy {
   typedef base::Callback<
       void(base::PlatformFileError result,
            const base::PlatformFileInfo& file_info,
-           const FilePath& platform_path,
+           const base::FilePath& platform_path,
            FileSystemFileUtil::SnapshotFilePolicy snapshot_policy)>
       SnapshotFileCallback;
 
@@ -85,7 +85,7 @@ class FileSystemFileUtilProxy {
   static bool CopyInForeignFile(
       FileSystemOperationContext* context,
       FileSystemFileUtil* file_util,
-      const FilePath& src_local_disk_file_path,
+      const base::FilePath& src_local_disk_file_path,
       const FileSystemURL& dest_url,
       const StatusCallback& callback);
 
diff --git a/webkit/fileapi/file_system_file_util_unittest.cc b/webkit/fileapi/file_system_file_util_unittest.cc
index b33b32a951bf63..9e12299e1cdbfe 100644
--- a/webkit/fileapi/file_system_file_util_unittest.cc
+++ b/webkit/fileapi/file_system_file_util_unittest.cc
@@ -116,7 +116,7 @@ class FileSystemFileUtilTest : public testing::Test {
           dest_root.path().Append(test_case.path));
 
       base::PlatformFileInfo dest_file_info;
-      FilePath data_path;
+      base::FilePath data_path;
       context.reset(NewContext(&dest_helper));
       EXPECT_EQ(base::PLATFORM_FILE_OK,
           file_util->GetFileInfo(
@@ -140,7 +140,7 @@ class FileSystemFileUtilTest : public testing::Test {
       FileSystemURL url = src_root.WithPath(
           src_root.path().Append(test_case.path));
       base::PlatformFileInfo src_file_info;
-      FilePath data_path;
+      base::FilePath data_path;
       context.reset(NewContext(&src_helper));
       base::PlatformFileError expected_result;
       if (copy)
diff --git a/webkit/fileapi/file_system_mount_point_provider.h b/webkit/fileapi/file_system_mount_point_provider.h
index 585b3cd9abca83..2e193727867123 100644
--- a/webkit/fileapi/file_system_mount_point_provider.h
+++ b/webkit/fileapi/file_system_mount_point_provider.h
@@ -56,7 +56,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemMountPointProvider {
   // file system url on the file thread.
   // If |create| is true this may also create the root directory for
   // the filesystem if it doesn't exist.
-  virtual FilePath GetFileSystemRootPathOnFileThread(
+  virtual base::FilePath GetFileSystemRootPathOnFileThread(
       const FileSystemURL& url,
       bool create) = 0;
 
@@ -65,7 +65,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemMountPointProvider {
 
   // Checks if a given |name| contains any restricted names/chars in it.
   // Callable on any thread.
-  virtual bool IsRestrictedFileName(const FilePath& filename) const = 0;
+  virtual bool IsRestrictedFileName(const base::FilePath& filename) const = 0;
 
   // Returns the specialized FileSystemFileUtil for this mount point.
   // It is ok to return NULL if the filesystem doesn't support synchronous
@@ -135,21 +135,21 @@ class ExternalFileSystemMountPointProvider
   // Returns the list of top level directories that are exposed by this
   // provider. This list is used to set appropriate child process file access
   // permissions.
-  virtual std::vector<FilePath> GetRootDirectories() const = 0;
+  virtual std::vector<base::FilePath> GetRootDirectories() const = 0;
   // Grants access to all external file system from extension identified with
   // |extension_id|.
   virtual void GrantFullAccessToExtension(const std::string& extension_id) = 0;
   // Grants access to |virtual_path| from |origin_url|.
   virtual void GrantFileAccessToExtension(
       const std::string& extension_id,
-      const FilePath& virtual_path) = 0;
+      const base::FilePath& virtual_path) = 0;
   // Revokes file access from extension identified with |extension_id|.
   virtual void RevokeAccessForExtension(
         const std::string& extension_id) = 0;
   // Gets virtual path by known filesystem path. Returns false when filesystem
   // path is not exposed by this provider.
-  virtual bool GetVirtualPath(const FilePath& file_system_path,
-                              FilePath* virtual_path) = 0;
+  virtual bool GetVirtualPath(const base::FilePath& file_system_path,
+                              base::FilePath* virtual_path) = 0;
 };
 
 }  // namespace fileapi
diff --git a/webkit/fileapi/file_system_mount_point_provider_unittest.cc b/webkit/fileapi/file_system_mount_point_provider_unittest.cc
index c36aa9bf57bfb3..e3abb477faf793 100644
--- a/webkit/fileapi/file_system_mount_point_provider_unittest.cc
+++ b/webkit/fileapi/file_system_mount_point_provider_unittest.cc
@@ -88,7 +88,7 @@ const struct RootPathFileURITest {
 };
 
 const struct CheckValidPathTest {
-  FilePath::StringType path;
+  base::FilePath::StringType path;
   bool expected_valid;
 } kCheckValidPathTestCases[] = {
   { FILE_PATH_LITERAL("//tmp/foo.txt"), false, },
@@ -102,7 +102,7 @@ const struct CheckValidPathTest {
 };
 
 const struct IsRestrictedNameTest {
-  FilePath::StringType name;
+  base::FilePath::StringType name;
   bool expected_dangerous;
 } kIsRestrictedNameTestCases[] = {
   // Names that contain strings that used to be restricted, but are now allowed.
@@ -193,9 +193,9 @@ const struct IsRestrictedNameTest {
 };
 
 // For External filesystem.
-const FilePath::CharType kMountPoint[] = FILE_PATH_LITERAL("/tmp/testing");
-const FilePath::CharType kRootPath[] = FILE_PATH_LITERAL("/tmp");
-const FilePath::CharType kVirtualPath[] = FILE_PATH_LITERAL("testing");
+const base::FilePath::CharType kMountPoint[] = FILE_PATH_LITERAL("/tmp/testing");
+const base::FilePath::CharType kRootPath[] = FILE_PATH_LITERAL("/tmp");
+const base::FilePath::CharType kVirtualPath[] = FILE_PATH_LITERAL("testing");
 
 }  // namespace
 
@@ -222,7 +222,7 @@ class FileSystemMountPointProviderTest : public testing::Test {
         data_dir_.path(),
         options);
 #if defined(OS_CHROMEOS)
-    FilePath mount_point_path = FilePath(kMountPoint);
+    base::FilePath mount_point_path = base::FilePath(kMountPoint);
     external_mount_points->RegisterFileSystem(
         mount_point_path.BaseName().AsUTF8Unsafe(),
         kFileSystemTypeNativeLocal,
@@ -238,21 +238,21 @@ class FileSystemMountPointProviderTest : public testing::Test {
   bool GetRootPath(const GURL& origin_url,
                    fileapi::FileSystemType type,
                    bool create,
-                   FilePath* root_path) {
-    FilePath virtual_path = FilePath();
+                   base::FilePath* root_path) {
+    base::FilePath virtual_path = base::FilePath();
     if (type == kFileSystemTypeExternal)
-      virtual_path = FilePath(kVirtualPath);
+      virtual_path = base::FilePath(kVirtualPath);
     FileSystemURL url = file_system_context_->CreateCrackedFileSystemURL(
         origin_url, type, virtual_path);
-    FilePath returned_root_path =
+    base::FilePath returned_root_path =
         provider(type)->GetFileSystemRootPathOnFileThread(url, create);
     if (root_path)
       *root_path = returned_root_path;
     return !returned_root_path.empty();
   }
 
-  FilePath data_path() const { return data_dir_.path(); }
-  FilePath file_system_path() const {
+  base::FilePath data_path() const { return data_dir_.path(); }
+  base::FilePath file_system_path() const {
     return data_dir_.path().Append(
         SandboxMountPointProvider::kFileSystemDirectory);
   }
@@ -272,7 +272,7 @@ class FileSystemMountPointProviderTest : public testing::Test {
 };
 
 TEST_F(FileSystemMountPointProviderTest, GetRootPathCreateAndExamine) {
-  std::vector<FilePath> returned_root_path(
+  std::vector<base::FilePath> returned_root_path(
       ARRAYSIZE_UNSAFE(kRootPathTestCases));
   SetupNewContext(CreateAllowFileAccessOptions());
 
@@ -281,13 +281,13 @@ TEST_F(FileSystemMountPointProviderTest, GetRootPathCreateAndExamine) {
     SCOPED_TRACE(testing::Message() << "RootPath (create) #" << i << " "
                  << kRootPathTestCases[i].expected_path);
 
-    FilePath root_path;
+    base::FilePath root_path;
     EXPECT_TRUE(GetRootPath(GURL(kRootPathTestCases[i].origin_url),
                             kRootPathTestCases[i].type,
                             true /* create */, &root_path));
 
     if (kRootPathTestCases[i].type != kFileSystemTypeExternal) {
-      FilePath expected = file_system_path().AppendASCII(
+      base::FilePath expected = file_system_path().AppendASCII(
           kRootPathTestCases[i].expected_path);
       EXPECT_EQ(expected.value(), root_path.value());
       EXPECT_TRUE(file_util::DirectoryExists(root_path));
@@ -306,7 +306,7 @@ TEST_F(FileSystemMountPointProviderTest, GetRootPathCreateAndExamine) {
     SCOPED_TRACE(testing::Message() << "RootPath (get) #" << i << " "
                  << kRootPathTestCases[i].expected_path);
 
-    FilePath root_path;
+    base::FilePath root_path;
     EXPECT_TRUE(GetRootPath(GURL(kRootPathTestCases[i].origin_url),
                             kRootPathTestCases[i].type,
                             false /* create */, &root_path));
@@ -317,18 +317,18 @@ TEST_F(FileSystemMountPointProviderTest, GetRootPathCreateAndExamine) {
 
 TEST_F(FileSystemMountPointProviderTest,
        GetRootPathCreateAndExamineWithNewProvider) {
-  std::vector<FilePath> returned_root_path(
+  std::vector<base::FilePath> returned_root_path(
       ARRAYSIZE_UNSAFE(kRootPathTestCases));
   SetupNewContext(CreateAllowFileAccessOptions());
 
   GURL origin_url("http://foo.com:1/");
 
-  FilePath root_path1;
+  base::FilePath root_path1;
   EXPECT_TRUE(GetRootPath(origin_url,
                           kFileSystemTypeTemporary, true, &root_path1));
 
   SetupNewContext(CreateDisallowFileAccessOptions());
-  FilePath root_path2;
+  base::FilePath root_path2;
   EXPECT_TRUE(GetRootPath(origin_url,
                           kFileSystemTypeTemporary, false, &root_path2));
 
@@ -383,11 +383,11 @@ TEST_F(FileSystemMountPointProviderTest, GetRootPathFileURIWithAllowFlag) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kRootPathFileURITestCases); ++i) {
     SCOPED_TRACE(testing::Message() << "RootPathFileURI (allow) #"
                  << i << " " << kRootPathFileURITestCases[i].expected_path);
-    FilePath root_path;
+    base::FilePath root_path;
     EXPECT_TRUE(GetRootPath(GURL(kRootPathFileURITestCases[i].origin_url),
                             kRootPathFileURITestCases[i].type,
                             true /* create */, &root_path));
-    FilePath expected = file_system_path().AppendASCII(
+    base::FilePath expected = file_system_path().AppendASCII(
         kRootPathFileURITestCases[i].expected_path);
     EXPECT_EQ(expected.value(), root_path.value());
     EXPECT_TRUE(file_util::DirectoryExists(root_path));
@@ -399,7 +399,7 @@ TEST_F(FileSystemMountPointProviderTest, IsRestrictedName) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kIsRestrictedNameTestCases); ++i) {
     SCOPED_TRACE(testing::Message() << "IsRestrictedName #" << i << " "
                  << kIsRestrictedNameTestCases[i].name);
-    FilePath name(kIsRestrictedNameTestCases[i].name);
+    base::FilePath name(kIsRestrictedNameTestCases[i].name);
     EXPECT_EQ(kIsRestrictedNameTestCases[i].expected_dangerous,
               provider(kFileSystemTypeTemporary)->IsRestrictedFileName(name));
   }
diff --git a/webkit/fileapi/file_system_operation.h b/webkit/fileapi/file_system_operation.h
index 5b2319419b78ae..21bdf40baf3d5b 100644
--- a/webkit/fileapi/file_system_operation.h
+++ b/webkit/fileapi/file_system_operation.h
@@ -64,7 +64,7 @@ class FileSystemOperation {
   typedef base::Callback<
       void(base::PlatformFileError result,
            const base::PlatformFileInfo& file_info,
-           const FilePath& platform_path)> GetMetadataCallback;
+           const base::FilePath& platform_path)> GetMetadataCallback;
 
   // Used for OpenFile(). |result| is the return code of the operation.
   typedef base::Callback<
@@ -107,7 +107,7 @@ class FileSystemOperation {
   typedef base::Callback<
       void(base::PlatformFileError result,
            const base::PlatformFileInfo& file_info,
-           const FilePath& platform_path,
+           const base::FilePath& platform_path,
            const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref)>
           SnapshotFileCallback;
 
diff --git a/webkit/fileapi/file_system_origin_database.cc b/webkit/fileapi/file_system_origin_database.cc
index 0c9207af568675..0300da24324f7f 100644
--- a/webkit/fileapi/file_system_origin_database.cc
+++ b/webkit/fileapi/file_system_origin_database.cc
@@ -20,7 +20,8 @@
 
 namespace {
 
-const FilePath::CharType kOriginDatabaseName[] = FILE_PATH_LITERAL("Origins");
+const base::FilePath::CharType kOriginDatabaseName[] =
+    FILE_PATH_LITERAL("Origins");
 const char kOriginKeyPrefix[] = "ORIGIN:";
 const char kLastPathKey[] = "LAST_PATH";
 const int64 kMinimumReportIntervalHours = 1;
@@ -51,7 +52,7 @@ FileSystemOriginDatabase::OriginRecord::OriginRecord() {
 }
 
 FileSystemOriginDatabase::OriginRecord::OriginRecord(
-    const std::string& origin_in, const FilePath& path_in)
+    const std::string& origin_in, const base::FilePath& path_in)
     : origin(origin_in), path(path_in) {
 }
 
@@ -59,7 +60,7 @@ FileSystemOriginDatabase::OriginRecord::~OriginRecord() {
 }
 
 FileSystemOriginDatabase::FileSystemOriginDatabase(
-    const FilePath& file_system_directory)
+    const base::FilePath& file_system_directory)
     : file_system_directory_(file_system_directory) {
 }
 
@@ -116,15 +117,15 @@ bool FileSystemOriginDatabase::RepairDatabase(const std::string& db_path) {
   }
 
   // See if the repaired entries match with what we have on disk.
-  std::set<FilePath> directories;
+  std::set<base::FilePath> directories;
   file_util::FileEnumerator file_enum(file_system_directory_,
                                       false /* recursive */,
                                       file_util::FileEnumerator::DIRECTORIES);
-  FilePath path_each;
+  base::FilePath path_each;
   while (!(path_each = file_enum.Next()).empty())
     directories.insert(path_each.BaseName());
-  std::set<FilePath>::iterator db_dir_itr =
-      directories.find(FilePath(kOriginDatabaseName));
+  std::set<base::FilePath>::iterator db_dir_itr =
+      directories.find(base::FilePath(kOriginDatabaseName));
   // Make sure we have the database file in its directory and therefore we are
   // working on the correct path.
   DCHECK(db_dir_itr != directories.end());
@@ -140,7 +141,7 @@ bool FileSystemOriginDatabase::RepairDatabase(const std::string& db_path) {
   for (std::vector<OriginRecord>::iterator db_origin_itr = origins.begin();
        db_origin_itr != origins.end();
        ++db_origin_itr) {
-    std::set<FilePath>::iterator dir_itr =
+    std::set<base::FilePath>::iterator dir_itr =
         directories.find(db_origin_itr->path);
     if (dir_itr == directories.end()) {
       if (!RemovePathForOrigin(db_origin_itr->origin)) {
@@ -153,7 +154,7 @@ bool FileSystemOriginDatabase::RepairDatabase(const std::string& db_path) {
   }
 
   // Delete any directories not listed in the origins database.
-  for (std::set<FilePath>::iterator dir_itr = directories.begin();
+  for (std::set<base::FilePath>::iterator dir_itr = directories.begin();
        dir_itr != directories.end();
        ++dir_itr) {
     if (!file_util::Delete(file_system_directory_.Append(*dir_itr),
@@ -214,7 +215,7 @@ bool FileSystemOriginDatabase::HasOriginPath(const std::string& origin) {
 }
 
 bool FileSystemOriginDatabase::GetPathForOrigin(
-    const std::string& origin, FilePath* directory) {
+    const std::string& origin, base::FilePath* directory) {
   if (!Init(REPAIR_ON_CORRUPTION))
     return false;
   DCHECK(directory);
@@ -271,7 +272,7 @@ bool FileSystemOriginDatabase::ListAllOrigins(
       StartsWithASCII(iter->key().ToString(), origin_key_prefix, true)) {
     std::string origin =
       iter->key().ToString().substr(origin_key_prefix.length());
-    FilePath path = StringToFilePath(iter->value().ToString());
+    base::FilePath path = StringToFilePath(iter->value().ToString());
     origins->push_back(OriginRecord(origin, path));
     iter->Next();
   }
diff --git a/webkit/fileapi/file_system_origin_database.h b/webkit/fileapi/file_system_origin_database.h
index ea71822ed6920b..98eb21281d6af8 100644
--- a/webkit/fileapi/file_system_origin_database.h
+++ b/webkit/fileapi/file_system_origin_database.h
@@ -31,23 +31,23 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemOriginDatabase {
  public:
   struct WEBKIT_STORAGE_EXPORT_PRIVATE OriginRecord {
     std::string origin;
-    FilePath path;
+    base::FilePath path;
 
     OriginRecord();
-    OriginRecord(const std::string& origin, const FilePath& path);
+    OriginRecord(const std::string& origin, const base::FilePath& path);
     ~OriginRecord();
   };
 
   // Only one instance of FileSystemOriginDatabase should exist for a given path
   // at a given time.
-  explicit FileSystemOriginDatabase(const FilePath& file_system_directory);
+  explicit FileSystemOriginDatabase(const base::FilePath& file_system_directory);
   ~FileSystemOriginDatabase();
 
   bool HasOriginPath(const std::string& origin);
 
   // This will produce a unique path and add it to its database, if it's not
   // already present.
-  bool GetPathForOrigin(const std::string& origin, FilePath* directory);
+  bool GetPathForOrigin(const std::string& origin, base::FilePath* directory);
 
   // Also returns success if the origin is not found.
   bool RemovePathForOrigin(const std::string& origin);
@@ -71,7 +71,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemOriginDatabase {
   void ReportInitStatus(const leveldb::Status& status);
   bool GetLastPathNumber(int* number);
 
-  FilePath file_system_directory_;
+  base::FilePath file_system_directory_;
   scoped_ptr<leveldb::DB> db_;
   base::Time last_reported_time_;
   DISALLOW_COPY_AND_ASSIGN(FileSystemOriginDatabase);
diff --git a/webkit/fileapi/file_system_origin_database_unittest.cc b/webkit/fileapi/file_system_origin_database_unittest.cc
index 695bea8d200035..e3cc8fbc56ce58 100644
--- a/webkit/fileapi/file_system_origin_database_unittest.cc
+++ b/webkit/fileapi/file_system_origin_database_unittest.cc
@@ -22,15 +22,15 @@
 namespace fileapi {
 
 namespace {
-const FilePath::CharType kFileSystemDirName[] =
+const base::FilePath::CharType kFileSystemDirName[] =
     FILE_PATH_LITERAL("File System");
-const FilePath::CharType kOriginDatabaseName[] = FILE_PATH_LITERAL("Origins");
+const base::FilePath::CharType kOriginDatabaseName[] = FILE_PATH_LITERAL("Origins");
 }  // namespace
 
 TEST(FileSystemOriginDatabaseTest, BasicTest) {
   base::ScopedTempDir dir;
   ASSERT_TRUE(dir.CreateUniqueTempDir());
-  const FilePath kFSDir = dir.path().Append(kFileSystemDirName);
+  const base::FilePath kFSDir = dir.path().Append(kFileSystemDirName);
   EXPECT_FALSE(file_util::PathExists(kFSDir));
   EXPECT_TRUE(file_util::CreateDirectory(kFSDir));
 
@@ -41,8 +41,8 @@ TEST(FileSystemOriginDatabaseTest, BasicTest) {
   // Double-check to make sure that had no side effects.
   EXPECT_FALSE(database.HasOriginPath(origin));
 
-  FilePath path0;
-  FilePath path1;
+  base::FilePath path0;
+  base::FilePath path1;
 
   // Empty strings aren't valid origins.
   EXPECT_FALSE(database.GetPathForOrigin(std::string(), &path0));
@@ -60,7 +60,7 @@ TEST(FileSystemOriginDatabaseTest, BasicTest) {
 TEST(FileSystemOriginDatabaseTest, TwoPathTest) {
   base::ScopedTempDir dir;
   ASSERT_TRUE(dir.CreateUniqueTempDir());
-  const FilePath kFSDir = dir.path().Append(kFileSystemDirName);
+  const base::FilePath kFSDir = dir.path().Append(kFileSystemDirName);
   EXPECT_FALSE(file_util::PathExists(kFSDir));
   EXPECT_TRUE(file_util::CreateDirectory(kFSDir));
 
@@ -71,8 +71,8 @@ TEST(FileSystemOriginDatabaseTest, TwoPathTest) {
   EXPECT_FALSE(database.HasOriginPath(origin0));
   EXPECT_FALSE(database.HasOriginPath(origin1));
 
-  FilePath path0;
-  FilePath path1;
+  base::FilePath path0;
+  base::FilePath path1;
   EXPECT_TRUE(database.GetPathForOrigin(origin0, &path0));
   EXPECT_TRUE(database.HasOriginPath(origin0));
   EXPECT_FALSE(database.HasOriginPath(origin1));
@@ -88,7 +88,7 @@ TEST(FileSystemOriginDatabaseTest, TwoPathTest) {
 TEST(FileSystemOriginDatabaseTest, DropDatabaseTest) {
   base::ScopedTempDir dir;
   ASSERT_TRUE(dir.CreateUniqueTempDir());
-  const FilePath kFSDir = dir.path().Append(kFileSystemDirName);
+  const base::FilePath kFSDir = dir.path().Append(kFileSystemDirName);
   EXPECT_FALSE(file_util::PathExists(kFSDir));
   EXPECT_TRUE(file_util::CreateDirectory(kFSDir));
 
@@ -97,7 +97,7 @@ TEST(FileSystemOriginDatabaseTest, DropDatabaseTest) {
 
   EXPECT_FALSE(database.HasOriginPath(origin));
 
-  FilePath path0;
+  base::FilePath path0;
   EXPECT_TRUE(database.GetPathForOrigin(origin, &path0));
   EXPECT_TRUE(database.HasOriginPath(origin));
   EXPECT_FALSE(path0.empty());
@@ -106,7 +106,7 @@ TEST(FileSystemOriginDatabaseTest, DropDatabaseTest) {
 
   database.DropDatabase();
 
-  FilePath path1;
+  base::FilePath path1;
   EXPECT_TRUE(database.HasOriginPath(origin));
   EXPECT_TRUE(database.GetPathForOrigin(origin, &path1));
   EXPECT_FALSE(path1.empty());
@@ -116,7 +116,7 @@ TEST(FileSystemOriginDatabaseTest, DropDatabaseTest) {
 TEST(FileSystemOriginDatabaseTest, DeleteOriginTest) {
   base::ScopedTempDir dir;
   ASSERT_TRUE(dir.CreateUniqueTempDir());
-  const FilePath kFSDir = dir.path().Append(kFileSystemDirName);
+  const base::FilePath kFSDir = dir.path().Append(kFileSystemDirName);
   EXPECT_FALSE(file_util::PathExists(kFSDir));
   EXPECT_TRUE(file_util::CreateDirectory(kFSDir));
 
@@ -126,7 +126,7 @@ TEST(FileSystemOriginDatabaseTest, DeleteOriginTest) {
   EXPECT_FALSE(database.HasOriginPath(origin));
   EXPECT_TRUE(database.RemovePathForOrigin(origin));
 
-  FilePath path0;
+  base::FilePath path0;
   EXPECT_TRUE(database.GetPathForOrigin(origin, &path0));
   EXPECT_TRUE(database.HasOriginPath(origin));
   EXPECT_FALSE(path0.empty());
@@ -134,7 +134,7 @@ TEST(FileSystemOriginDatabaseTest, DeleteOriginTest) {
   EXPECT_TRUE(database.RemovePathForOrigin(origin));
   EXPECT_FALSE(database.HasOriginPath(origin));
 
-  FilePath path1;
+  base::FilePath path1;
   EXPECT_TRUE(database.GetPathForOrigin(origin, &path1));
   EXPECT_FALSE(path1.empty());
   EXPECT_NE(path0, path1);
@@ -143,7 +143,7 @@ TEST(FileSystemOriginDatabaseTest, DeleteOriginTest) {
 TEST(FileSystemOriginDatabaseTest, ListOriginsTest) {
   base::ScopedTempDir dir;
   ASSERT_TRUE(dir.CreateUniqueTempDir());
-  const FilePath kFSDir = dir.path().Append(kFileSystemDirName);
+  const base::FilePath kFSDir = dir.path().Append(kFileSystemDirName);
   EXPECT_FALSE(file_util::PathExists(kFSDir));
   EXPECT_TRUE(file_util::CreateDirectory(kFSDir));
 
@@ -160,8 +160,8 @@ TEST(FileSystemOriginDatabaseTest, ListOriginsTest) {
   EXPECT_FALSE(database.HasOriginPath(origin0));
   EXPECT_FALSE(database.HasOriginPath(origin1));
 
-  FilePath path0;
-  FilePath path1;
+  base::FilePath path0;
+  base::FilePath path1;
   EXPECT_TRUE(database.GetPathForOrigin(origin0, &path0));
   EXPECT_TRUE(database.ListAllOrigins(&origins));
   EXPECT_EQ(origins.size(), 1UL);
@@ -192,8 +192,8 @@ TEST(FileSystemOriginDatabaseTest, DatabaseRecoveryTest) {
 
   base::ScopedTempDir dir;
   ASSERT_TRUE(dir.CreateUniqueTempDir());
-  const FilePath kFSDir = dir.path().Append(kFileSystemDirName);
-  const FilePath kDBDir = kFSDir.Append(kOriginDatabaseName);
+  const base::FilePath kFSDir = dir.path().Append(kFileSystemDirName);
+  const base::FilePath kDBDir = kFSDir.Append(kOriginDatabaseName);
   EXPECT_FALSE(file_util::PathExists(kFSDir));
   EXPECT_TRUE(file_util::CreateDirectory(kFSDir));
 
@@ -208,7 +208,7 @@ TEST(FileSystemOriginDatabaseTest, DatabaseRecoveryTest) {
   scoped_ptr<FileSystemOriginDatabase> database(
       new FileSystemOriginDatabase(kFSDir));
   for (size_t i = 0; i < arraysize(kOrigins); ++i) {
-    FilePath path;
+    base::FilePath path;
     EXPECT_FALSE(database->HasOriginPath(kOrigins[i]));
     EXPECT_TRUE(database->GetPathForOrigin(kOrigins[i], &path));
     EXPECT_FALSE(path.empty());
@@ -219,8 +219,8 @@ TEST(FileSystemOriginDatabaseTest, DatabaseRecoveryTest) {
   }
   database.reset();
 
-  const FilePath kGarbageDir = kFSDir.AppendASCII("foo");
-  const FilePath kGarbageFile = kGarbageDir.AppendASCII("bar");
+  const base::FilePath kGarbageDir = kFSDir.AppendASCII("foo");
+  const base::FilePath kGarbageFile = kGarbageDir.AppendASCII("bar");
   EXPECT_TRUE(file_util::CreateDirectory(kGarbageDir));
   bool created = false;
   base::PlatformFileError error;
@@ -239,7 +239,7 @@ TEST(FileSystemOriginDatabaseTest, DatabaseRecoveryTest) {
                   0, std::numeric_limits<size_t>::max());
   CorruptDatabase(kDBDir, leveldb::kLogFile, -1, 1);
 
-  FilePath path;
+  base::FilePath path;
   database.reset(new FileSystemOriginDatabase(kFSDir));
   std::vector<FileSystemOriginDatabase::OriginRecord> origins_in_db;
   EXPECT_TRUE(database->ListAllOrigins(&origins_in_db));
diff --git a/webkit/fileapi/file_system_quota_client_unittest.cc b/webkit/fileapi/file_system_quota_client_unittest.cc
index ae858e0c4a0948..8859ddda442b52 100644
--- a/webkit/fileapi/file_system_quota_client_unittest.cc
+++ b/webkit/fileapi/file_system_quota_client_unittest.cc
@@ -129,7 +129,7 @@ class FileSystemQuotaClientTest : public testing::Test {
     return context;
   }
 
-  bool CreateFileSystemDirectory(const FilePath& file_path,
+  bool CreateFileSystemDirectory(const base::FilePath& file_path,
                                  const std::string& origin_url,
                                  quota::StorageType storage_type) {
     FileSystemType type = QuotaStorageTypeToFileSystemType(storage_type);
@@ -147,7 +147,7 @@ class FileSystemQuotaClientTest : public testing::Test {
     return true;
   }
 
-  bool CreateFileSystemFile(const FilePath& file_path,
+  bool CreateFileSystemFile(const base::FilePath& file_path,
                             int64 file_size,
                             const std::string& origin_url,
                             quota::StorageType storage_type) {
@@ -178,7 +178,7 @@ class FileSystemQuotaClientTest : public testing::Test {
                              const TestFile* files,
                              int num_files) {
     for (int i = 0; i < num_files; i++) {
-      FilePath path = FilePath().AppendASCII(files[i].name);
+      base::FilePath path = base::FilePath().AppendASCII(files[i].name);
       if (files[i].isDirectory) {
         ASSERT_TRUE(CreateFileSystemDirectory(
             path, files[i].origin_url, files[i].type));
@@ -210,7 +210,7 @@ class FileSystemQuotaClientTest : public testing::Test {
     for (int i = 0; i < num_files; i++) {
       if (files[i].type == type &&
           GURL(files[i].origin_url) == GURL(origin_url)) {
-        FilePath path = FilePath().AppendASCII(files[i].name);
+        base::FilePath path = base::FilePath().AppendASCII(files[i].name);
         if (!path.empty()) {
           file_paths_cost += ObfuscatedFileUtil::ComputeFilePathCost(path);
         }
diff --git a/webkit/fileapi/file_system_url.cc b/webkit/fileapi/file_system_url.cc
index 7d88f141cbed83..5f38e53dabfdc3 100644
--- a/webkit/fileapi/file_system_url.cc
+++ b/webkit/fileapi/file_system_url.cc
@@ -21,7 +21,7 @@ namespace {
 bool ParseFileSystemURL(const GURL& url,
                         GURL* origin_url,
                         FileSystemType* type,
-                        FilePath* file_path) {
+                        base::FilePath* file_path) {
   GURL origin;
   FileSystemType file_system_type = kFileSystemTypeUnknown;
 
@@ -60,7 +60,7 @@ bool ParseFileSystemURL(const GURL& url,
   while (!path.empty() && path[0] == '/')
     path.erase(0, 1);
 
-  FilePath converted_path = FilePath::FromUTF8Unsafe(path);
+  base::FilePath converted_path = base::FilePath::FromUTF8Unsafe(path);
 
   // All parent references should have been resolved in the renderer.
   if (converted_path.ReferencesParent())
@@ -92,7 +92,7 @@ FileSystemURL FileSystemURL::CreateForTest(const GURL& url) {
 
 FileSystemURL FileSystemURL::CreateForTest(const GURL& origin,
                                            FileSystemType type,
-                                           const FilePath& path) {
+                                           const base::FilePath& path) {
   return FileSystemURL(origin, type, path);
 }
 
@@ -105,7 +105,7 @@ FileSystemURL::FileSystemURL(const GURL& url)
 
 FileSystemURL::FileSystemURL(const GURL& origin,
                              FileSystemType type,
-                             const FilePath& path)
+                             const base::FilePath& path)
     : is_valid_(true),
       origin_(origin),
       type_(type),
@@ -115,10 +115,10 @@ FileSystemURL::FileSystemURL(const GURL& origin,
 
 FileSystemURL::FileSystemURL(const GURL& origin,
                              FileSystemType original_type,
-                             const FilePath& original_path,
+                             const base::FilePath& original_path,
                              const std::string& filesystem_id,
                              FileSystemType cracked_type,
-                             const FilePath& cracked_path)
+                             const base::FilePath& cracked_path)
     : is_valid_(true),
       origin_(origin),
       type_(cracked_type),
@@ -149,7 +149,7 @@ std::string FileSystemURL::DebugString() const {
   return ss.str();
 }
 
-FileSystemURL FileSystemURL::WithPath(const FilePath& path) const {
+FileSystemURL FileSystemURL::WithPath(const base::FilePath& path) const {
   FileSystemURL url = *this;
   url.path_ = path;
   url.virtual_path_.clear();
diff --git a/webkit/fileapi/file_system_url.h b/webkit/fileapi/file_system_url.h
index 0245d94126f2e4..99b187b019cd19 100644
--- a/webkit/fileapi/file_system_url.h
+++ b/webkit/fileapi/file_system_url.h
@@ -62,11 +62,11 @@ namespace fileapi {
 // one of the friended classes.
 //
 // TODO(ericu): Look into making path() [and all FileSystem API virtual
-// paths] just an std::string, to prevent platform-specific FilePath behavior
-// from getting invoked by accident. Currently the FilePath returned here needs
+// paths] just an std::string, to prevent platform-specific base::FilePath behavior
+// from getting invoked by accident. Currently the base::FilePath returned here needs
 // special treatment, as it may contain paths that are illegal on the current
 // platform.  To avoid problems, use VirtualPath::BaseName and
-// VirtualPath::GetComponents instead of the FilePath methods.
+// VirtualPath::GetComponents instead of the base::FilePath methods.
 class WEBKIT_STORAGE_EXPORT FileSystemURL {
  public:
   FileSystemURL();
@@ -77,7 +77,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemURL {
   static FileSystemURL CreateForTest(const GURL& url);
   static FileSystemURL CreateForTest(const GURL& origin,
                                      FileSystemType type,
-                                     const FilePath& path);
+                                     const base::FilePath& path);
 
   // Returns true if this instance represents a valid FileSystem URL.
   bool is_valid() const { return is_valid_; }
@@ -90,12 +90,12 @@ class WEBKIT_STORAGE_EXPORT FileSystemURL {
 
   // Returns the path part of this URL. See the class comment for details.
   // TODO(kinuko): this must return std::string.
-  const FilePath& path() const { return path_; }
+  const base::FilePath& path() const { return path_; }
 
   // Returns the original path part of this URL.
   // See the class comment for details.
   // TODO(kinuko): this must return std::string.
-  const FilePath& virtual_path() const { return virtual_path_; }
+  const base::FilePath& virtual_path() const { return virtual_path_; }
 
   // Returns the filesystem ID/mount name for isolated/external filesystem URLs.
   // See the class comment for details.
@@ -112,7 +112,7 @@ class WEBKIT_STORAGE_EXPORT FileSystemURL {
   // Note that the resulting FileSystemURL loses original URL information
   // if it was a cracked filesystem; i.e. virtual_path and mount_type will
   // be set to empty values.
-  FileSystemURL WithPath(const FilePath& path) const;
+  FileSystemURL WithPath(const base::FilePath& path) const;
 
   // Returns true if this URL is a strict parent of the |child|.
   bool IsParent(const FileSystemURL& child) const;
@@ -131,25 +131,25 @@ class WEBKIT_STORAGE_EXPORT FileSystemURL {
   explicit FileSystemURL(const GURL& filesystem_url);
   FileSystemURL(const GURL& origin,
                 FileSystemType type,
-                const FilePath& internal_path);
+                const base::FilePath& internal_path);
   // Creates a cracked FileSystemURL.
   FileSystemURL(const GURL& origin,
                 FileSystemType original_type,
-                const FilePath& original_path,
+                const base::FilePath& original_path,
                 const std::string& filesystem_id,
                 FileSystemType cracked_type,
-                const FilePath& cracked_path);
+                const base::FilePath& cracked_path);
 
   bool is_valid_;
 
   GURL origin_;
   FileSystemType type_;
   FileSystemType mount_type_;
-  FilePath path_;
+  base::FilePath path_;
 
   // Values specific to cracked URLs.
   std::string filesystem_id_;
-  FilePath virtual_path_;
+  base::FilePath virtual_path_;
 
 };
 
diff --git a/webkit/fileapi/file_system_url_request_job.cc b/webkit/fileapi/file_system_url_request_job.cc
index 18bf7380ce098d..4db776ad45c15b 100644
--- a/webkit/fileapi/file_system_url_request_job.cc
+++ b/webkit/fileapi/file_system_url_request_job.cc
@@ -117,7 +117,7 @@ bool FileSystemURLRequestJob::ReadRawData(net::IOBuffer* dest, int dest_size,
 bool FileSystemURLRequestJob::GetMimeType(std::string* mime_type) const {
   DCHECK(request_);
   DCHECK(url_.is_valid());
-  FilePath::StringType extension = url_.path().Extension();
+  base::FilePath::StringType extension = url_.path().Extension();
   if (!extension.empty())
     extension = extension.substr(1);
   return net::GetWellKnownMimeTypeFromExtension(extension, mime_type);
@@ -174,7 +174,7 @@ void FileSystemURLRequestJob::StartAsync() {
 void FileSystemURLRequestJob::DidGetMetadata(
     base::PlatformFileError error_code,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   if (error_code != base::PLATFORM_FILE_OK) {
     NotifyFailed(error_code == base::PLATFORM_FILE_ERROR_INVALID_URL ?
                  net::ERR_INVALID_URL : net::ERR_FILE_NOT_FOUND);
diff --git a/webkit/fileapi/file_system_url_request_job.h b/webkit/fileapi/file_system_url_request_job.h
index 5b6e42dda07c9c..55f6e70b47a3aa 100644
--- a/webkit/fileapi/file_system_url_request_job.h
+++ b/webkit/fileapi/file_system_url_request_job.h
@@ -17,7 +17,10 @@
 #include "webkit/storage/webkit_storage_export.h"
 
 class GURL;
+
+namespace base {
 class FilePath;
+}
 
 namespace webkit_blob {
 class FileStreamReader;
@@ -60,7 +63,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemURLRequestJob
   void DidGetMetadata(
       base::PlatformFileError error_code,
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path);
+      const base::FilePath& platform_path);
   void DidRead(int result);
   void NotifyFailed(int rv);
 
diff --git a/webkit/fileapi/file_system_url_request_job_unittest.cc b/webkit/fileapi/file_system_url_request_job_unittest.cc
index 5168886fac6448..b142d6caa01424 100644
--- a/webkit/fileapi/file_system_url_request_job_unittest.cc
+++ b/webkit/fileapi/file_system_url_request_job_unittest.cc
@@ -138,7 +138,7 @@ class FileSystemURLRequestJobTest : public testing::Test {
     FileSystemURL url = file_system_context_->CreateCrackedFileSystemURL(
         GURL("http://remote"),
         kFileSystemTypeTemporary,
-        FilePath().AppendASCII(dir_name));
+        base::FilePath().AppendASCII(dir_name));
 
     FileSystemOperationContext context(file_system_context_);
     context.set_allowed_bytes_growth(1024);
@@ -157,7 +157,7 @@ class FileSystemURLRequestJobTest : public testing::Test {
     FileSystemURL url = file_system_context_->CreateCrackedFileSystemURL(
         GURL("http://remote"),
         kFileSystemTypeTemporary,
-        FilePath().AppendASCII(file_name));
+        base::FilePath().AppendASCII(file_name));
 
     FileSystemOperationContext context(file_system_context_);
     context.set_allowed_bytes_growth(1024);
@@ -353,8 +353,8 @@ TEST_F(FileSystemURLRequestJobTest, GetMimeType) {
   const char kFilename[] = "hoge.html";
 
   std::string mime_type_direct;
-  FilePath::StringType extension =
-      FilePath().AppendASCII(kFilename).Extension();
+  base::FilePath::StringType extension =
+      base::FilePath().AppendASCII(kFilename).Extension();
   if (!extension.empty())
     extension = extension.substr(1);
   EXPECT_TRUE(net::GetWellKnownMimeTypeFromExtension(
diff --git a/webkit/fileapi/file_system_url_unittest.cc b/webkit/fileapi/file_system_url_unittest.cc
index 58a4b7a5862f75..158f768b225b2f 100644
--- a/webkit/fileapi/file_system_url_unittest.cc
+++ b/webkit/fileapi/file_system_url_unittest.cc
@@ -41,12 +41,12 @@ FileSystemURL CreateFileSystemURL(const std::string& url_string) {
 
 FileSystemURL CreateExternalFileSystemURL(const GURL& origin,
                                           FileSystemType type,
-                                          const FilePath& path) {
+                                          const base::FilePath& path) {
   return ExternalMountPoints::GetSystemInstance()->CreateCrackedFileSystemURL(
       origin, type, path);
 }
 
-std::string NormalizedUTF8Path(const FilePath& path) {
+std::string NormalizedUTF8Path(const base::FilePath& path) {
   return path.NormalizePathSeparators().AsUTF8Unsafe();
 }
 
@@ -140,7 +140,7 @@ TEST(FileSystemURLTest, CompareURLs) {
 
 TEST(FileSystemURLTest, WithPath) {
   const GURL kURL("filesystem:http://chromium.org/temporary/dir");
-  const FilePath::StringType paths[] = {
+  const base::FilePath::StringType paths[] = {
       FPL("dir a"),
       FPL("dir a/file 1"),
       FPL("dir a/dir b"),
@@ -149,7 +149,7 @@ TEST(FileSystemURLTest, WithPath) {
 
   const FileSystemURL base = FileSystemURL::CreateForTest(kURL);
   for (size_t i = 0; i < arraysize(paths); ++i) {
-    const FileSystemURL url = base.WithPath(FilePath(paths[i]));
+    const FileSystemURL url = base.WithPath(base::FilePath(paths[i]));
     EXPECT_EQ(paths[i], url.path().value());
     EXPECT_EQ(base.origin().spec(), url.origin().spec());
     EXPECT_EQ(base.type(), url.type());
@@ -160,11 +160,11 @@ TEST(FileSystemURLTest, WithPath) {
 
 TEST(FileSystemURLTest, WithPathForExternal) {
   const std::string kId = "foo";
-  ScopedExternalFileSystem scoped_fs(kId, kFileSystemTypeSyncable, FilePath());
-  const FilePath kVirtualRoot = scoped_fs.GetVirtualRootPath();
+  ScopedExternalFileSystem scoped_fs(kId, kFileSystemTypeSyncable, base::FilePath());
+  const base::FilePath kVirtualRoot = scoped_fs.GetVirtualRootPath();
 
-  const FilePath::CharType kBasePath[] = FPL("dir");
-  const FilePath::StringType paths[] = {
+  const base::FilePath::CharType kBasePath[] = FPL("dir");
+  const base::FilePath::StringType paths[] = {
       FPL("dir a"),
       FPL("dir a/file 1"),
       FPL("dir a/dir b"),
@@ -177,7 +177,7 @@ TEST(FileSystemURLTest, WithPathForExternal) {
       kVirtualRoot.Append(kBasePath));
 
   for (size_t i = 0; i < arraysize(paths); ++i) {
-    const FileSystemURL url = base.WithPath(FilePath(paths[i]));
+    const FileSystemURL url = base.WithPath(base::FilePath(paths[i]));
     EXPECT_EQ(paths[i], url.path().value());
     EXPECT_EQ(base.origin().spec(), url.origin().spec());
     EXPECT_EQ(base.type(), url.type());
@@ -187,8 +187,8 @@ TEST(FileSystemURLTest, WithPathForExternal) {
 }
 
 TEST(FileSystemURLTest, IsParent) {
-  ScopedExternalFileSystem scoped1("foo", kFileSystemTypeSyncable, FilePath());
-  ScopedExternalFileSystem scoped2("bar", kFileSystemTypeSyncable, FilePath());
+  ScopedExternalFileSystem scoped1("foo", kFileSystemTypeSyncable, base::FilePath());
+  ScopedExternalFileSystem scoped2("bar", kFileSystemTypeSyncable, base::FilePath());
 
   const std::string root1 = GetFileSystemRootURI(
       GURL("http://example.com"), kFileSystemTypeTemporary).spec();
@@ -232,7 +232,7 @@ TEST(FileSystemURLTest, IsParent) {
 
 TEST(FileSystemURLTest, DebugString) {
   const GURL kOrigin("http://example.com");
-  const FilePath kPath(FPL("dir/file"));
+  const base::FilePath kPath(FPL("dir/file"));
 
   const FileSystemURL kURL1 = FileSystemURL::CreateForTest(
       kOrigin, kFileSystemTypeTemporary, kPath);
@@ -240,7 +240,7 @@ TEST(FileSystemURLTest, DebugString) {
             NormalizedUTF8Path(kPath),
             kURL1.DebugString());
 
-  const FilePath kRoot(DRIVE FPL("/root"));
+  const base::FilePath kRoot(DRIVE FPL("/root"));
   ScopedExternalFileSystem scoped_fs("foo",
                                      kFileSystemTypeNativeLocal,
                                      kRoot.NormalizePathSeparators());
diff --git a/webkit/fileapi/file_system_usage_cache.cc b/webkit/fileapi/file_system_usage_cache.cc
index 1c5e824bcbc583..fedb79e675ac3b 100644
--- a/webkit/fileapi/file_system_usage_cache.cc
+++ b/webkit/fileapi/file_system_usage_cache.cc
@@ -10,7 +10,7 @@
 
 namespace fileapi {
 
-const FilePath::CharType FileSystemUsageCache::kUsageFileName[] =
+const base::FilePath::CharType FileSystemUsageCache::kUsageFileName[] =
     FILE_PATH_LITERAL(".usage");
 const char FileSystemUsageCache::kUsageFileHeader[] = "FSU5";
 const int FileSystemUsageCache::kUsageFileHeaderSize = 4;
@@ -22,7 +22,7 @@ const int FileSystemUsageCache::kUsageFileSize =
     sizeof(int) + sizeof(int32) + sizeof(int64);
 
 // static
-int64 FileSystemUsageCache::GetUsage(const FilePath& usage_file_path) {
+int64 FileSystemUsageCache::GetUsage(const base::FilePath& usage_file_path) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 fs_usage;
@@ -35,7 +35,7 @@ int64 FileSystemUsageCache::GetUsage(const FilePath& usage_file_path) {
 }
 
 // static
-int32 FileSystemUsageCache::GetDirty(const FilePath& usage_file_path) {
+int32 FileSystemUsageCache::GetDirty(const base::FilePath& usage_file_path) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 fs_usage;
@@ -48,7 +48,7 @@ int32 FileSystemUsageCache::GetDirty(const FilePath& usage_file_path) {
 }
 
 // static
-bool FileSystemUsageCache::IncrementDirty(const FilePath& usage_file_path) {
+bool FileSystemUsageCache::IncrementDirty(const base::FilePath& usage_file_path) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 fs_usage;
@@ -61,7 +61,7 @@ bool FileSystemUsageCache::IncrementDirty(const FilePath& usage_file_path) {
 }
 
 // static
-bool FileSystemUsageCache::DecrementDirty(const FilePath& usage_file_path) {
+bool FileSystemUsageCache::DecrementDirty(const base::FilePath& usage_file_path) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 fs_usage;
@@ -74,7 +74,7 @@ bool FileSystemUsageCache::DecrementDirty(const FilePath& usage_file_path) {
 }
 
 // static
-bool FileSystemUsageCache::Invalidate(const FilePath& usage_file_path) {
+bool FileSystemUsageCache::Invalidate(const base::FilePath& usage_file_path) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 fs_usage;
@@ -83,7 +83,7 @@ bool FileSystemUsageCache::Invalidate(const FilePath& usage_file_path) {
   return fs_usage >= 0 && Write(usage_file_path, false, dirty, fs_usage);
 }
 
-bool FileSystemUsageCache::IsValid(const FilePath& usage_file_path) {
+bool FileSystemUsageCache::IsValid(const base::FilePath& usage_file_path) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 result = Read(usage_file_path, &is_valid, &dirty);
@@ -95,7 +95,7 @@ bool FileSystemUsageCache::IsValid(const FilePath& usage_file_path) {
 
 // static
 int FileSystemUsageCache::AtomicUpdateUsageByDelta(
-    const FilePath& usage_file_path, int64 delta) {
+    const base::FilePath& usage_file_path, int64 delta) {
   bool is_valid = true;
   uint32 dirty = 0;
   int64 fs_usage;
@@ -109,23 +109,23 @@ int FileSystemUsageCache::AtomicUpdateUsageByDelta(
 }
 
 // static
-int FileSystemUsageCache::UpdateUsage(const FilePath& usage_file_path,
+int FileSystemUsageCache::UpdateUsage(const base::FilePath& usage_file_path,
                                       int64 fs_usage) {
   return Write(usage_file_path, true, 0, fs_usage);
 }
 
 // static
-bool FileSystemUsageCache::Exists(const FilePath& usage_file_path) {
+bool FileSystemUsageCache::Exists(const base::FilePath& usage_file_path) {
   return file_util::PathExists(usage_file_path);
 }
 
 // static
-bool FileSystemUsageCache::Delete(const FilePath& usage_file_path) {
+bool FileSystemUsageCache::Delete(const base::FilePath& usage_file_path) {
   return file_util::Delete(usage_file_path, true);
 }
 
 // static
-int64 FileSystemUsageCache::Read(const FilePath& usage_file_path,
+int64 FileSystemUsageCache::Read(const base::FilePath& usage_file_path,
                                  bool* is_valid,
                                  uint32* dirty) {
   char buffer[kUsageFileSize];
@@ -154,7 +154,7 @@ int64 FileSystemUsageCache::Read(const FilePath& usage_file_path,
 }
 
 // static
-int FileSystemUsageCache::Write(const FilePath& usage_file_path,
+int FileSystemUsageCache::Write(const base::FilePath& usage_file_path,
                                 bool is_valid,
                                 uint32 dirty,
                                 int64 fs_usage) {
@@ -164,7 +164,7 @@ int FileSystemUsageCache::Write(const FilePath& usage_file_path,
   write_pickle.WriteUInt32(dirty);
   write_pickle.WriteInt64(fs_usage);
 
-  FilePath temporary_usage_file_path;
+  base::FilePath temporary_usage_file_path;
   if (usage_file_path.empty() ||
       !file_util::CreateTemporaryFileInDir(usage_file_path.DirName(),
                                            &temporary_usage_file_path)) {
diff --git a/webkit/fileapi/file_system_usage_cache.h b/webkit/fileapi/file_system_usage_cache.h
index 3d25120d9fbe28..428aa4b3dd747e 100644
--- a/webkit/fileapi/file_system_usage_cache.h
+++ b/webkit/fileapi/file_system_usage_cache.h
@@ -16,34 +16,34 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemUsageCache {
   // Gets the size described in the .usage file even if dirty > 0 or
   // is_valid == false.  Returns less than zero if the .usage file is not
   // available.
-  static int64 GetUsage(const FilePath& usage_file_path);
+  static int64 GetUsage(const base::FilePath& usage_file_path);
 
   // Gets the dirty count in the .usage file.
   // Returns less than zero if the .usage file is not available.
-  static int32 GetDirty(const FilePath& usage_file_path);
+  static int32 GetDirty(const base::FilePath& usage_file_path);
 
   // Increments or decrements the "dirty" entry in the .usage file.
   // Returns false if no .usage is available.
-  static bool IncrementDirty(const FilePath& usage_file_path);
-  static bool DecrementDirty(const FilePath& usage_file_path);
+  static bool IncrementDirty(const base::FilePath& usage_file_path);
+  static bool DecrementDirty(const base::FilePath& usage_file_path);
 
   // Notifies quota system that it needs to recalculate the usage cache of the
   // origin.  Returns false if no .usage is available.
-  static bool Invalidate(const FilePath& usage_file_path);
-  static bool IsValid(const FilePath& usage_file_path);
+  static bool Invalidate(const base::FilePath& usage_file_path);
+  static bool IsValid(const base::FilePath& usage_file_path);
 
   // Updates the size described in the .usage file.
-  static int UpdateUsage(const FilePath& usage_file_path, int64 fs_usage);
+  static int UpdateUsage(const base::FilePath& usage_file_path, int64 fs_usage);
 
   // Updates the size described in the .usage file by delta with keeping dirty
   // even if dirty > 0.
   static int AtomicUpdateUsageByDelta(
-      const FilePath& usage_file_path, int64 delta);
+      const base::FilePath& usage_file_path, int64 delta);
 
-  static bool Exists(const FilePath& usage_file_path);
-  static bool Delete(const FilePath& usage_file_path);
+  static bool Exists(const base::FilePath& usage_file_path);
+  static bool Delete(const base::FilePath& usage_file_path);
 
-  static const FilePath::CharType kUsageFileName[];
+  static const base::FilePath::CharType kUsageFileName[];
   static const char kUsageFileHeader[];
   static const int kUsageFileSize;
   static const int kUsageFileHeaderSize;
@@ -51,11 +51,11 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE FileSystemUsageCache {
  private:
   // Read the size, validity and the "dirty" entry described in the .usage file.
   // Returns less than zero if no .usage file is available.
-  static int64 Read(const FilePath& usage_file_path,
+  static int64 Read(const base::FilePath& usage_file_path,
                     bool* is_valid,
                     uint32* dirty);
 
-  static int Write(const FilePath& usage_file_path,
+  static int Write(const base::FilePath& usage_file_path,
                    bool is_valid,
                    uint32 dirty,
                    int64 fs_usage);
diff --git a/webkit/fileapi/file_system_usage_cache_unittest.cc b/webkit/fileapi/file_system_usage_cache_unittest.cc
index 8662dc87742351..edc445786bc68a 100644
--- a/webkit/fileapi/file_system_usage_cache_unittest.cc
+++ b/webkit/fileapi/file_system_usage_cache_unittest.cc
@@ -20,7 +20,7 @@ class FileSystemUsageCacheTest : public testing::Test {
   }
 
  protected:
-  FilePath GetUsageFilePath() {
+  base::FilePath GetUsageFilePath() {
     return data_dir_.path().Append(FileSystemUsageCache::kUsageFileName);
   }
 
@@ -31,14 +31,14 @@ class FileSystemUsageCacheTest : public testing::Test {
 };
 
 TEST_F(FileSystemUsageCacheTest, CreateTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   EXPECT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, 0));
 }
 
 TEST_F(FileSystemUsageCacheTest, SetSizeTest) {
   static const int64 size = 240122;
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, size));
   EXPECT_EQ(size, FileSystemUsageCache::GetUsage(usage_file_path));
@@ -46,14 +46,14 @@ TEST_F(FileSystemUsageCacheTest, SetSizeTest) {
 
 TEST_F(FileSystemUsageCacheTest, SetLargeSizeTest) {
   static const int64 size = kint64max;
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, size));
   EXPECT_EQ(size, FileSystemUsageCache::GetUsage(usage_file_path));
 }
 
 TEST_F(FileSystemUsageCacheTest, IncAndGetSizeTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, 98214));
   ASSERT_TRUE(FileSystemUsageCache::IncrementDirty(usage_file_path));
@@ -63,7 +63,7 @@ TEST_F(FileSystemUsageCacheTest, IncAndGetSizeTest) {
 
 TEST_F(FileSystemUsageCacheTest, DecAndGetSizeTest) {
   static const int64 size = 71839;
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, size));
   // DecrementDirty for dirty = 0 is invalid. It returns false.
@@ -73,7 +73,7 @@ TEST_F(FileSystemUsageCacheTest, DecAndGetSizeTest) {
 
 TEST_F(FileSystemUsageCacheTest, IncDecAndGetSizeTest) {
   static const int64 size = 198491;
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, size));
   ASSERT_TRUE(FileSystemUsageCache::IncrementDirty(usage_file_path));
@@ -82,7 +82,7 @@ TEST_F(FileSystemUsageCacheTest, IncDecAndGetSizeTest) {
 }
 
 TEST_F(FileSystemUsageCacheTest, DecIncAndGetSizeTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, 854238));
   // DecrementDirty for dirty = 0 is invalid. It returns false.
@@ -96,7 +96,7 @@ TEST_F(FileSystemUsageCacheTest, DecIncAndGetSizeTest) {
 
 TEST_F(FileSystemUsageCacheTest, ManyIncsSameDecsAndGetSizeTest) {
   static const int64 size = 82412;
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, size));
   for (int i = 0; i < 20; i++)
@@ -107,7 +107,7 @@ TEST_F(FileSystemUsageCacheTest, ManyIncsSameDecsAndGetSizeTest) {
 }
 
 TEST_F(FileSystemUsageCacheTest, ManyIncsLessDecsAndGetSizeTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   ASSERT_EQ(FileSystemUsageCache::kUsageFileSize,
             FileSystemUsageCache::UpdateUsage(usage_file_path, 19319));
   for (int i = 0; i < 20; i++)
@@ -119,17 +119,17 @@ TEST_F(FileSystemUsageCacheTest, ManyIncsLessDecsAndGetSizeTest) {
 }
 
 TEST_F(FileSystemUsageCacheTest, GetSizeWithoutCacheFileTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   EXPECT_EQ(-1, FileSystemUsageCache::GetUsage(usage_file_path));
 }
 
 TEST_F(FileSystemUsageCacheTest, IncrementDirtyWithoutCacheFileTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   EXPECT_FALSE(FileSystemUsageCache::IncrementDirty(usage_file_path));
 }
 
 TEST_F(FileSystemUsageCacheTest, DecrementDirtyWithoutCacheFileTest) {
-  FilePath usage_file_path = GetUsageFilePath();
+  base::FilePath usage_file_path = GetUsageFilePath();
   EXPECT_FALSE(FileSystemUsageCache::IncrementDirty(usage_file_path));
 }
 
diff --git a/webkit/fileapi/file_system_util.cc b/webkit/fileapi/file_system_util.cc
index 07db1534c3daf9..7e017f7afc8d73 100644
--- a/webkit/fileapi/file_system_util.cc
+++ b/webkit/fileapi/file_system_util.cc
@@ -27,26 +27,26 @@ const char kTestDir[] = "/test";
 
 // TODO(ericu): Consider removing support for '\', even on Windows, if possible.
 // There's a lot of test code that will need reworking, and we may have trouble
-// with FilePath elsewhere [e.g. DirName and other methods may also need
+// with base::FilePath elsewhere [e.g. DirName and other methods may also need
 // replacement].
-FilePath VirtualPath::BaseName(const FilePath& virtual_path) {
-  FilePath::StringType path = virtual_path.value();
+base::FilePath VirtualPath::BaseName(const base::FilePath& virtual_path) {
+  base::FilePath::StringType path = virtual_path.value();
 
   // Keep everything after the final separator, but if the pathname is only
   // one character and it's a separator, leave it alone.
-  while (path.size() > 1 && FilePath::IsSeparator(path[path.size() - 1]))
+  while (path.size() > 1 && base::FilePath::IsSeparator(path[path.size() - 1]))
     path.resize(path.size() - 1);
-  FilePath::StringType::size_type last_separator =
-      path.find_last_of(FilePath::kSeparators);
-  if (last_separator != FilePath::StringType::npos &&
+  base::FilePath::StringType::size_type last_separator =
+      path.find_last_of(base::FilePath::kSeparators);
+  if (last_separator != base::FilePath::StringType::npos &&
       last_separator < path.size() - 1)
     path.erase(0, last_separator + 1);
 
-  return FilePath(path);
+  return base::FilePath(path);
 }
 
 void VirtualPath::GetComponents(
-    const FilePath& path, std::vector<FilePath::StringType>* components) {
+    const base::FilePath& path, std::vector<base::FilePath::StringType>* components) {
   DCHECK(components);
   if (!components)
     return;
@@ -54,12 +54,12 @@ void VirtualPath::GetComponents(
   if (path.value().empty())
     return;
 
-  std::vector<FilePath::StringType> ret_val;
-  FilePath current = path;
-  FilePath base;
+  std::vector<base::FilePath::StringType> ret_val;
+  base::FilePath current = path;
+  base::FilePath base;
 
-  // Due to the way things are implemented, FilePath::DirName works here,
-  // whereas FilePath::BaseName doesn't.
+  // Due to the way things are implemented, base::FilePath::DirName works here,
+  // whereas base::FilePath::BaseName doesn't.
   while (current != current.DirName()) {
     base = BaseName(current);
     ret_val.push_back(base.value());
@@ -67,7 +67,7 @@ void VirtualPath::GetComponents(
   }
 
   *components =
-      std::vector<FilePath::StringType>(ret_val.rbegin(), ret_val.rend());
+      std::vector<base::FilePath::StringType>(ret_val.rbegin(), ret_val.rend());
 }
 
 GURL GetFileSystemRootURI(const GURL& origin_url, FileSystemType type) {
@@ -193,7 +193,7 @@ std::string GetFileSystemTypeString(FileSystemType type) {
   return std::string();
 }
 
-std::string FilePathToString(const FilePath& file_path) {
+std::string FilePathToString(const base::FilePath& file_path) {
 #if defined(OS_WIN)
   return UTF16ToUTF8(file_path.value());
 #elif defined(OS_POSIX)
@@ -201,11 +201,11 @@ std::string FilePathToString(const FilePath& file_path) {
 #endif
 }
 
-FilePath StringToFilePath(const std::string& file_path_string) {
+base::FilePath StringToFilePath(const std::string& file_path_string) {
 #if defined(OS_WIN)
-  return FilePath(UTF8ToUTF16(file_path_string));
+  return base::FilePath(UTF8ToUTF16(file_path_string));
 #elif defined(OS_POSIX)
-  return FilePath(file_path_string);
+  return base::FilePath(file_path_string);
 #endif
 }
 
@@ -282,7 +282,7 @@ std::string GetIsolatedFileSystemRootURIString(
   root.append(filesystem_id);
   root.append("/");
   if (!optional_root_name.empty()) {
-    DCHECK(!FilePath::FromUTF8Unsafe(optional_root_name).ReferencesParent());
+    DCHECK(!base::FilePath::FromUTF8Unsafe(optional_root_name).ReferencesParent());
     root.append(optional_root_name);
     root.append("/");
   }
diff --git a/webkit/fileapi/file_system_util.h b/webkit/fileapi/file_system_util.h
index b8bc41fb634279..be863bfed9769d 100644
--- a/webkit/fileapi/file_system_util.h
+++ b/webkit/fileapi/file_system_util.h
@@ -27,17 +27,17 @@ extern const char kTestDir[];
 
 class WEBKIT_STORAGE_EXPORT VirtualPath {
  public:
-  // Use this instead of FilePath::BaseName when operating on virtual paths.
-  // FilePath::BaseName will get confused by ':' on Windows when it looks like a
+  // Use this instead of base::FilePath::BaseName when operating on virtual paths.
+  // base::FilePath::BaseName will get confused by ':' on Windows when it looks like a
   // drive letter separator; this will treat it as just another character.
-  static FilePath BaseName(const FilePath& virtual_path);
+  static base::FilePath BaseName(const base::FilePath& virtual_path);
 
-  // Likewise, use this instead of FilePath::GetComponents when operating on
+  // Likewise, use this instead of base::FilePath::GetComponents when operating on
   // virtual paths.
   // Note that this assumes very clean input, with no leading slash, and it will
   // not evaluate '.' or '..' components.
-  static void GetComponents(const FilePath& path,
-      std::vector<FilePath::StringType>* components);
+  static void GetComponents(const base::FilePath& path,
+      std::vector<base::FilePath::StringType>* components);
 };
 
 // Returns the root URI of the filesystem that can be specified by a pair of
@@ -99,10 +99,10 @@ WEBKIT_STORAGE_EXPORT std::string GetFileSystemTypeString(FileSystemType type);
 //
 // TODO(tzik): Replace CreateFilePath and FilePathToString in
 // third_party/leveldatabase/env_chromium.cc with them.
-WEBKIT_STORAGE_EXPORT std::string FilePathToString(const FilePath& file_path);
+WEBKIT_STORAGE_EXPORT std::string FilePathToString(const base::FilePath& file_path);
 
 // Decode a file path from |file_path_string|.
-WEBKIT_STORAGE_EXPORT FilePath StringToFilePath(
+WEBKIT_STORAGE_EXPORT base::FilePath StringToFilePath(
     const std::string& file_path_string);
 
 // File error conversion
diff --git a/webkit/fileapi/file_system_util_unittest.cc b/webkit/fileapi/file_system_util_unittest.cc
index 946e75f08a37d7..0fd4f0a45ed861 100644
--- a/webkit/fileapi/file_system_util_unittest.cc
+++ b/webkit/fileapi/file_system_util_unittest.cc
@@ -30,8 +30,8 @@ TEST_F(FileSystemUtilTest, GetPersistentFileSystemRootURI) {
 
 TEST_F(FileSystemUtilTest, VirtualPathBaseName) {
   struct test_data {
-    const FilePath::StringType path;
-    const FilePath::StringType base_name;
+    const base::FilePath::StringType path;
+    const base::FilePath::StringType base_name;
   } test_cases[] = {
     { FILE_PATH_LITERAL("foo/bar"), FILE_PATH_LITERAL("bar") },
     { FILE_PATH_LITERAL("foo/b:bar"), FILE_PATH_LITERAL("b:bar") },
@@ -48,17 +48,17 @@ TEST_F(FileSystemUtilTest, VirtualPathBaseName) {
     { FILE_PATH_LITERAL("bar"), FILE_PATH_LITERAL("bar") }
   };
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
-    FilePath input = FilePath(test_cases[i].path);
-    FilePath base_name = VirtualPath::BaseName(input);
+    base::FilePath input = base::FilePath(test_cases[i].path);
+    base::FilePath base_name = VirtualPath::BaseName(input);
     EXPECT_EQ(test_cases[i].base_name, base_name.value());
   }
 }
 
 TEST_F(FileSystemUtilTest, VirtualPathGetComponents) {
   struct test_data {
-    const FilePath::StringType path;
+    const base::FilePath::StringType path;
     size_t count;
-    const FilePath::StringType components[3];
+    const base::FilePath::StringType components[3];
   } test_cases[] = {
     { FILE_PATH_LITERAL("foo/bar"),
       2,
@@ -83,8 +83,8 @@ TEST_F(FileSystemUtilTest, VirtualPathGetComponents) {
       { FILE_PATH_LITERAL("foo"), FILE_PATH_LITERAL("bar") } },
   };
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
-    FilePath input = FilePath(test_cases[i].path);
-    std::vector<FilePath::StringType> components;
+    base::FilePath input = base::FilePath(test_cases[i].path);
+    std::vector<base::FilePath::StringType> components;
     VirtualPath::GetComponents(input, &components);
     EXPECT_EQ(test_cases[i].count, components.size());
     for (size_t j = 0; j < components.size(); ++j)
diff --git a/webkit/fileapi/file_util_helper.cc b/webkit/fileapi/file_util_helper.cc
index 2582f8a012d62d..49ea72c3cad458 100644
--- a/webkit/fileapi/file_util_helper.cc
+++ b/webkit/fileapi/file_util_helper.cc
@@ -21,20 +21,20 @@ namespace {
 // A helper class to delete a temporary file.
 class ScopedFileDeleter {
  public:
-  explicit ScopedFileDeleter(const FilePath& path) : path_(path) {}
+  explicit ScopedFileDeleter(const base::FilePath& path) : path_(path) {}
   ~ScopedFileDeleter() {
     file_util::Delete(path_, false /* recursive */);
   }
 
  private:
-  FilePath path_;
+  base::FilePath path_;
 };
 
 bool IsInRoot(const FileSystemURL& url) {
   // If path is in the root, path.DirName() will be ".",
   // since we use paths with no leading '/'.
-  FilePath parent = url.path().DirName();
-  return parent.empty() || parent == FilePath(FILE_PATH_LITERAL("."));
+  base::FilePath parent = url.path().DirName();
+  return parent.empty() || parent == base::FilePath(FILE_PATH_LITERAL("."));
 }
 
 // A helper class for cross-FileUtil Copy/Move operations.
@@ -160,7 +160,7 @@ PlatformFileError CrossFileUtilHelper::CopyOrMoveDirectory(
   // Store modified timestamp of the root directory.
   if (operation_ == OPERATION_MOVE) {
     base::PlatformFileInfo file_info;
-    FilePath platform_file_path;
+    base::FilePath platform_file_path;
     error = src_util_->GetFileInfo(
         context_, src_url, &file_info, &platform_file_path);
     if (error != base::PLATFORM_FILE_OK)
@@ -173,9 +173,9 @@ PlatformFileError CrossFileUtilHelper::CopyOrMoveDirectory(
       src_util_->CreateFileEnumerator(context_,
                                       src_url,
                                       true /* recursive */));
-  FilePath src_file_path_each;
+  base::FilePath src_file_path_each;
   while (!(src_file_path_each = file_enum->Next()).empty()) {
-    FilePath dest_file_path_each(dest_url.path());
+    base::FilePath dest_file_path_each(dest_url.path());
     src_url.path().AppendRelativePath(
         src_file_path_each, &dest_file_path_each);
 
@@ -229,7 +229,7 @@ PlatformFileError CrossFileUtilHelper::CopyOrMoveFile(
 
   // Resolve the src_url's underlying file path.
   base::PlatformFileInfo file_info;
-  FilePath platform_file_path;
+  base::FilePath platform_file_path;
   SnapshotFilePolicy snapshot_policy;
 
   PlatformFileError error = src_util_->CreateSnapshotFile(
@@ -265,7 +265,7 @@ bool FileUtilHelper::DirectoryExists(FileSystemOperationContext* context,
     return true;
 
   base::PlatformFileInfo file_info;
-  FilePath platform_path;
+  base::FilePath platform_path;
   PlatformFileError error = file_util->GetFileInfo(
       context, url, &file_info, &platform_path);
   return error == base::PLATFORM_FILE_OK && file_info.is_directory;
@@ -320,7 +320,7 @@ base::PlatformFileError FileUtilHelper::ReadDirectory(
   DCHECK(entries);
 
   base::PlatformFileInfo file_info;
-  FilePath platform_path;
+  base::FilePath platform_path;
   PlatformFileError error = file_util->GetFileInfo(
       context, url, &file_info, &platform_path);
   if (error != base::PLATFORM_FILE_OK)
@@ -331,7 +331,7 @@ base::PlatformFileError FileUtilHelper::ReadDirectory(
   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> file_enum(
       file_util->CreateFileEnumerator(context, url, false /* recursive */));
 
-  FilePath current;
+  base::FilePath current;
   while (!(current = file_enum->Next()).empty()) {
     base::FileUtilProxy::Entry entry;
     entry.is_directory = file_enum->IsDirectory();
@@ -351,8 +351,8 @@ base::PlatformFileError FileUtilHelper::DeleteDirectoryRecursive(
 
   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> file_enum(
       file_util->CreateFileEnumerator(context, url, true /* recursive */));
-  FilePath file_path_each;
-  std::stack<FilePath> directories;
+  base::FilePath file_path_each;
+  std::stack<base::FilePath> directories;
   while (!(file_path_each = file_enum->Next()).empty()) {
     if (file_enum->IsDirectory()) {
       directories.push(file_path_each);
diff --git a/webkit/fileapi/file_writer_delegate_unittest.cc b/webkit/fileapi/file_writer_delegate_unittest.cc
index 8a3fdf87da0ce7..fa40da0d984ad6 100644
--- a/webkit/fileapi/file_writer_delegate_unittest.cc
+++ b/webkit/fileapi/file_writer_delegate_unittest.cc
@@ -197,7 +197,7 @@ net::URLRequestJob* FileWriterDelegateTest::Factory(
 
 void FileWriterDelegateTest::SetUp() {
   ASSERT_TRUE(dir_.CreateUniqueTempDir());
-  FilePath base_dir = dir_.path().AppendASCII("filesystem");
+  base::FilePath base_dir = dir_.path().AppendASCII("filesystem");
   test_helper_.SetUp(base_dir);
 
   scoped_ptr<FileSystemOperationContext> context(
diff --git a/webkit/fileapi/isolated_context.cc b/webkit/fileapi/isolated_context.cc
index fe1aec0ce3000f..12232ce77cb8c6 100644
--- a/webkit/fileapi/isolated_context.cc
+++ b/webkit/fileapi/isolated_context.cc
@@ -18,15 +18,15 @@ namespace fileapi {
 
 namespace {
 
-FilePath::StringType GetRegisterNameForPath(const FilePath& path) {
+base::FilePath::StringType GetRegisterNameForPath(const base::FilePath& path) {
   // If it's not a root path simply return a base name.
   if (path.DirName() != path)
     return path.BaseName().value();
 
 #if defined(FILE_PATH_USES_DRIVE_LETTERS)
-  FilePath::StringType name;
+  base::FilePath::StringType name;
   for (size_t i = 0;
-        i < path.value().size() && !FilePath::IsSeparator(path.value()[i]);
+        i < path.value().size() && !base::FilePath::IsSeparator(path.value()[i]);
         ++i) {
     if (path.value()[i] == L':') {
       name.append(L"_drive");
@@ -67,19 +67,19 @@ IsolatedContext::FileInfoSet::FileInfoSet() {}
 IsolatedContext::FileInfoSet::~FileInfoSet() {}
 
 bool IsolatedContext::FileInfoSet::AddPath(
-    const FilePath& path, std::string* registered_name) {
+    const base::FilePath& path, std::string* registered_name) {
   // The given path should not contain any '..' and should be absolute.
   if (path.ReferencesParent() || !path.IsAbsolute())
     return false;
-  FilePath::StringType name = GetRegisterNameForPath(path);
-  std::string utf8name = FilePath(name).AsUTF8Unsafe();
-  FilePath normalized_path = path.NormalizePathSeparators();
+  base::FilePath::StringType name = GetRegisterNameForPath(path);
+  std::string utf8name = base::FilePath(name).AsUTF8Unsafe();
+  base::FilePath normalized_path = path.NormalizePathSeparators();
   bool inserted =
       fileset_.insert(MountPointInfo(utf8name, normalized_path)).second;
   if (!inserted) {
     int suffix = 1;
-    std::string basepart = FilePath(name).RemoveExtension().AsUTF8Unsafe();
-    std::string ext = FilePath(FilePath(name).Extension()).AsUTF8Unsafe();
+    std::string basepart = base::FilePath(name).RemoveExtension().AsUTF8Unsafe();
+    std::string ext = base::FilePath(base::FilePath(name).Extension()).AsUTF8Unsafe();
     while (!inserted) {
       utf8name = base::StringPrintf("%s (%d)", basepart.c_str(), suffix++);
       if (!ext.empty())
@@ -94,7 +94,7 @@ bool IsolatedContext::FileInfoSet::AddPath(
 }
 
 bool IsolatedContext::FileInfoSet::AddPathWithName(
-    const FilePath& path, const std::string& name) {
+    const base::FilePath& path, const std::string& name) {
   // The given path should not contain any '..' and should be absolute.
   if (path.ReferencesParent() || !path.IsAbsolute())
     return false;
@@ -126,7 +126,7 @@ class IsolatedContext::Instance {
   void AddRef() { ++ref_counts_; }
   void RemoveRef() { --ref_counts_; }
 
-  bool ResolvePathForName(const std::string& name, FilePath* path) const;
+  bool ResolvePathForName(const std::string& name, base::FilePath* path) const;
 
   // Returns true if the instance is a single-path instance.
   bool IsSinglePathInstance() const;
@@ -166,13 +166,13 @@ IsolatedContext::Instance::Instance(FileSystemType type,
 IsolatedContext::Instance::~Instance() {}
 
 bool IsolatedContext::Instance::ResolvePathForName(const std::string& name,
-                                                   FilePath* path) const {
+                                                   base::FilePath* path) const {
   if (IsSinglePathIsolatedFileSystem(type_)) {
     *path = file_info_.path;
     return file_info_.name == name;
   }
   std::set<MountPointInfo>::const_iterator found = files_.find(
-      MountPointInfo(name, FilePath()));
+      MountPointInfo(name, base::FilePath()));
   if (found == files_.end())
     return false;
   *path = found->path;
@@ -206,15 +206,15 @@ std::string IsolatedContext::RegisterDraggedFileSystem(
 
 std::string IsolatedContext::RegisterFileSystemForPath(
     FileSystemType type,
-    const FilePath& path_in,
+    const base::FilePath& path_in,
     std::string* register_name) {
-  FilePath path(path_in.NormalizePathSeparators());
+  base::FilePath path(path_in.NormalizePathSeparators());
   DCHECK(!path.ReferencesParent() && path.IsAbsolute());
   std::string name;
   if (register_name && !register_name->empty()) {
     name = *register_name;
   } else {
-    name = FilePath(GetRegisterNameForPath(path)).AsUTF8Unsafe();
+    name = base::FilePath(GetRegisterNameForPath(path)).AsUTF8Unsafe();
     if (register_name)
       register_name->assign(name);
   }
@@ -236,7 +236,7 @@ bool IsolatedContext::RevokeFileSystem(const std::string& filesystem_id) {
 }
 
 bool IsolatedContext::GetRegisteredPath(
-    const std::string& filesystem_id, FilePath* path) const {
+    const std::string& filesystem_id, base::FilePath* path) const {
   DCHECK(path);
   base::AutoLock locker(lock_);
   IDToInstance::const_iterator found = instance_map_.find(filesystem_id);
@@ -246,10 +246,10 @@ bool IsolatedContext::GetRegisteredPath(
   return true;
 }
 
-bool IsolatedContext::CrackVirtualPath(const FilePath& virtual_path,
+bool IsolatedContext::CrackVirtualPath(const base::FilePath& virtual_path,
                                         std::string* id_or_name,
                                         FileSystemType* type,
-                                        FilePath* path) const {
+                                        base::FilePath* path) const {
   DCHECK(id_or_name);
   DCHECK(path);
 
@@ -258,17 +258,17 @@ bool IsolatedContext::CrackVirtualPath(const FilePath& virtual_path,
     return false;
 
   // The virtual_path should comprise <id_or_name> and <relative_path> parts.
-  std::vector<FilePath::StringType> components;
+  std::vector<base::FilePath::StringType> components;
   virtual_path.GetComponents(&components);
   if (components.size() < 1)
     return false;
-  std::vector<FilePath::StringType>::iterator component_iter =
+  std::vector<base::FilePath::StringType>::iterator component_iter =
       components.begin();
-  std::string fsid = FilePath(*component_iter++).MaybeAsASCII();
+  std::string fsid = base::FilePath(*component_iter++).MaybeAsASCII();
   if (fsid.empty())
     return false;
 
-  FilePath cracked_path;
+  base::FilePath cracked_path;
   {
     base::AutoLock locker(lock_);
     IDToInstance::const_iterator found_instance = instance_map_.find(fsid);
@@ -286,7 +286,7 @@ bool IsolatedContext::CrackVirtualPath(const FilePath& virtual_path,
     }
 
     // *component_iter should be a name of the registered path.
-    std::string name = FilePath(*component_iter++).AsUTF8Unsafe();
+    std::string name = base::FilePath(*component_iter++).AsUTF8Unsafe();
     if (!instance->ResolvePathForName(name, &cracked_path))
       return false;
   }
@@ -309,13 +309,13 @@ FileSystemURL IsolatedContext::CrackURL(const GURL& url) const {
 FileSystemURL IsolatedContext::CreateCrackedFileSystemURL(
     const GURL& origin,
     FileSystemType type,
-    const FilePath& path) const {
+    const base::FilePath& path) const {
   if (!HandlesFileSystemMountType(type))
     return FileSystemURL();
 
   std::string mount_name;
   FileSystemType cracked_type;
-  FilePath cracked_path;
+  base::FilePath cracked_path;
   if (!CrackVirtualPath(path, &mount_name, &cracked_type, &cracked_path))
     return FileSystemURL();
 
@@ -323,9 +323,9 @@ FileSystemURL IsolatedContext::CreateCrackedFileSystemURL(
                        mount_name, cracked_type, cracked_path);
 }
 
-void IsolatedContext::RevokeFileSystemByPath(const FilePath& path_in) {
+void IsolatedContext::RevokeFileSystemByPath(const base::FilePath& path_in) {
   base::AutoLock locker(lock_);
-  FilePath path(path_in.NormalizePathSeparators());
+  base::FilePath path(path_in.NormalizePathSeparators());
   PathToID::iterator ids_iter = path_to_id_map_.find(path);
   if (ids_iter == path_to_id_map_.end())
     return;
@@ -377,9 +377,9 @@ bool IsolatedContext::GetDraggedFileInfo(
   return true;
 }
 
-FilePath IsolatedContext::CreateVirtualRootPath(
+base::FilePath IsolatedContext::CreateVirtualRootPath(
     const std::string& filesystem_id) const {
-  return FilePath().AppendASCII(filesystem_id);
+  return base::FilePath().AppendASCII(filesystem_id);
 }
 
 IsolatedContext::IsolatedContext() {
diff --git a/webkit/fileapi/isolated_context.h b/webkit/fileapi/isolated_context.h
index d679bc3c889910..faf034c323d5a4 100644
--- a/webkit/fileapi/isolated_context.h
+++ b/webkit/fileapi/isolated_context.h
@@ -48,12 +48,12 @@ class WEBKIT_STORAGE_EXPORT IsolatedContext : public MountPoints {
     // the registered name assigned for the path. |path| needs to be
     // absolute and should not contain parent references.
     // Return false if the |path| is not valid and could not be added.
-    bool AddPath(const FilePath& path, std::string* registered_name);
+    bool AddPath(const base::FilePath& path, std::string* registered_name);
 
     // Add the given |path| with the |name|.
     // Return false if the |name| is already registered in the set or
     // is not valid and could not be added.
-    bool AddPathWithName(const FilePath& path, const std::string& name);
+    bool AddPathWithName(const base::FilePath& path, const std::string& name);
 
     const std::set<MountPointInfo>& fileset() const { return fileset_; }
 
@@ -99,7 +99,7 @@ class WEBKIT_STORAGE_EXPORT IsolatedContext : public MountPoints {
   // registered as the given |register_name|, otherwise it is populated
   // with the name internally assigned to the path.
   std::string RegisterFileSystemForPath(FileSystemType type,
-                                        const FilePath& path,
+                                        const base::FilePath& path,
                                         std::string* register_name);
 
   // Revokes all filesystem(s) registered for the given path.
@@ -110,7 +110,7 @@ class WEBKIT_STORAGE_EXPORT IsolatedContext : public MountPoints {
   // It is ok to call this for the path that has no associated filesystems.
   // Note that this only works for the filesystems registered by
   // |RegisterFileSystemForPath|.
-  void RevokeFileSystemByPath(const FilePath& path);
+  void RevokeFileSystemByPath(const base::FilePath& path);
 
   // Adds a reference to a filesystem specified by the given filesystem_id.
   void AddReference(const std::string& filesystem_id);
@@ -133,19 +133,19 @@ class WEBKIT_STORAGE_EXPORT IsolatedContext : public MountPoints {
   virtual bool HandlesFileSystemMountType(FileSystemType type) const OVERRIDE;
   virtual bool RevokeFileSystem(const std::string& filesystem_id) OVERRIDE;
   virtual bool GetRegisteredPath(const std::string& filesystem_id,
-                                 FilePath* path) const OVERRIDE;
-  virtual bool CrackVirtualPath(const FilePath& virtual_path,
+                                 base::FilePath* path) const OVERRIDE;
+  virtual bool CrackVirtualPath(const base::FilePath& virtual_path,
                                 std::string* filesystem_id,
                                 FileSystemType* type,
-                                FilePath* path) const OVERRIDE;
+                                base::FilePath* path) const OVERRIDE;
   virtual FileSystemURL CrackURL(const GURL& url) const OVERRIDE;
   virtual FileSystemURL CreateCrackedFileSystemURL(
       const GURL& origin,
       FileSystemType type,
-      const FilePath& path) const OVERRIDE;
+      const base::FilePath& path) const OVERRIDE;
 
   // Returns the virtual root path that looks like /<filesystem_id>.
-  FilePath CreateVirtualRootPath(const std::string& filesystem_id) const;
+  base::FilePath CreateVirtualRootPath(const std::string& filesystem_id) const;
 
  private:
   friend struct base::DefaultLazyInstanceTraits<IsolatedContext>;
@@ -156,7 +156,7 @@ class WEBKIT_STORAGE_EXPORT IsolatedContext : public MountPoints {
   typedef std::map<std::string, Instance*> IDToInstance;
 
   // Reverse map from registered path to IDs.
-  typedef std::map<FilePath, std::set<std::string> > PathToID;
+  typedef std::map<base::FilePath, std::set<std::string> > PathToID;
 
   // Obtain an instance of this class via GetInstance().
   IsolatedContext();
diff --git a/webkit/fileapi/isolated_context_unittest.cc b/webkit/fileapi/isolated_context_unittest.cc
index 4cb7a84d2e4261..c2c9537ac0117f 100644
--- a/webkit/fileapi/isolated_context_unittest.cc
+++ b/webkit/fileapi/isolated_context_unittest.cc
@@ -24,19 +24,19 @@ typedef IsolatedContext::MountPointInfo FileInfo;
 
 namespace {
 
-const FilePath kTestPaths[] = {
-  FilePath(DRIVE FPL("/a/b.txt")),
-  FilePath(DRIVE FPL("/c/d/e")),
-  FilePath(DRIVE FPL("/h/")),
-  FilePath(DRIVE FPL("/")),
+const base::FilePath kTestPaths[] = {
+  base::FilePath(DRIVE FPL("/a/b.txt")),
+  base::FilePath(DRIVE FPL("/c/d/e")),
+  base::FilePath(DRIVE FPL("/h/")),
+  base::FilePath(DRIVE FPL("/")),
 #if defined(FILE_PATH_USES_WIN_SEPARATORS)
-  FilePath(DRIVE FPL("\\foo\\bar")),
-  FilePath(DRIVE FPL("\\")),
+  base::FilePath(DRIVE FPL("\\foo\\bar")),
+  base::FilePath(DRIVE FPL("\\")),
 #endif
   // For duplicated base name test.
-  FilePath(DRIVE FPL("/")),
-  FilePath(DRIVE FPL("/f/e")),
-  FilePath(DRIVE FPL("/f/b.txt")),
+  base::FilePath(DRIVE FPL("/")),
+  base::FilePath(DRIVE FPL("/f/e")),
+  base::FilePath(DRIVE FPL("/f/b.txt")),
 };
 
 }  // namespace
@@ -71,7 +71,7 @@ class IsolatedContextTest : public testing::Test {
 
  protected:
   std::string id_;
-  std::multiset<FilePath> fileset_;
+  std::multiset<base::FilePath> fileset_;
   std::vector<std::string> names_;
 
  private:
@@ -91,10 +91,10 @@ TEST_F(IsolatedContextTest, RegisterAndRevokeTest) {
   // register in SetUp() by RegisterDraggedFileSystem) is properly cracked as
   // a valid virtual path in the isolated filesystem.
   for (size_t i = 0; i < arraysize(kTestPaths); ++i) {
-    FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_)
+    base::FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_)
         .AppendASCII(names_[i]);
     std::string cracked_id;
-    FilePath cracked_path;
+    base::FilePath cracked_path;
     FileSystemType cracked_type;
     ASSERT_TRUE(isolated_context()->CrackVirtualPath(
         virtual_path, &cracked_id, &cracked_type, &cracked_path));
@@ -106,14 +106,14 @@ TEST_F(IsolatedContextTest, RegisterAndRevokeTest) {
 
   // Make sure GetRegisteredPath returns false for id_ since it is
   // registered for dragged files.
-  FilePath path;
+  base::FilePath path;
   ASSERT_FALSE(isolated_context()->GetRegisteredPath(id_, &path));
 
   // Deref the current one and registering a new one.
   isolated_context()->RemoveReference(id_);
 
   std::string id2 = isolated_context()->RegisterFileSystemForPath(
-      kFileSystemTypeNativeLocal, FilePath(DRIVE FPL("/foo")), NULL);
+      kFileSystemTypeNativeLocal, base::FilePath(DRIVE FPL("/foo")), NULL);
 
   // Make sure the GetDraggedFileInfo returns false for both ones.
   ASSERT_FALSE(isolated_context()->GetDraggedFileInfo(id2, &toplevels));
@@ -165,7 +165,7 @@ TEST_F(IsolatedContextTest, RegisterAndRevokeTest) {
 
 TEST_F(IsolatedContextTest, CrackWithRelativePaths) {
   const struct {
-    FilePath::StringType path;
+    base::FilePath::StringType path;
     bool valid;
   } relatives[] = {
     { FPL("foo"), true },
@@ -186,10 +186,10 @@ TEST_F(IsolatedContextTest, CrackWithRelativePaths) {
     for (size_t j = 0; j < ARRAYSIZE_UNSAFE(relatives); ++j) {
       SCOPED_TRACE(testing::Message() << "Testing "
                    << kTestPaths[i].value() << " " << relatives[j].path);
-      FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_)
+      base::FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_)
           .AppendASCII(names_[i]).Append(relatives[j].path);
       std::string cracked_id;
-      FilePath cracked_path;
+      base::FilePath cracked_path;
       FileSystemType cracked_type;
       if (!relatives[j].valid) {
         ASSERT_FALSE(isolated_context()->CrackVirtualPath(
@@ -209,7 +209,7 @@ TEST_F(IsolatedContextTest, CrackWithRelativePaths) {
 
 TEST_F(IsolatedContextTest, CrackURLWithRelativePaths) {
   const struct {
-    FilePath::StringType path;
+    base::FilePath::StringType path;
     bool valid;
   } relatives[] = {
     { FPL("foo"), true },
@@ -230,7 +230,7 @@ TEST_F(IsolatedContextTest, CrackURLWithRelativePaths) {
     for (size_t j = 0; j < ARRAYSIZE_UNSAFE(relatives); ++j) {
       SCOPED_TRACE(testing::Message() << "Testing "
                    << kTestPaths[i].value() << " " << relatives[j].path);
-      FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_)
+      base::FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_)
           .AppendASCII(names_[i]).Append(relatives[j].path);
 
       FileSystemURL cracked = isolated_context()->CreateCrackedFileSystemURL(
@@ -254,12 +254,12 @@ TEST_F(IsolatedContextTest, CrackURLWithRelativePaths) {
 
 TEST_F(IsolatedContextTest, TestWithVirtualRoot) {
   std::string cracked_id;
-  FilePath cracked_path;
+  base::FilePath cracked_path;
 
   // Trying to crack virtual root "/" returns true but with empty cracked path
   // as "/" of the isolated filesystem is a pure virtual directory
   // that has no corresponding platform directory.
-  FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_);
+  base::FilePath virtual_path = isolated_context()->CreateVirtualRootPath(id_);
   ASSERT_TRUE(isolated_context()->CrackVirtualPath(
       virtual_path, &cracked_id, NULL, &cracked_path));
   ASSERT_EQ(FPL(""), cracked_path.value());
@@ -275,7 +275,7 @@ TEST_F(IsolatedContextTest, TestWithVirtualRoot) {
 
 TEST_F(IsolatedContextTest, CanHandleURL) {
   const GURL test_origin("http://chromium.org");
-  const FilePath test_path(FPL("/mount"));
+  const base::FilePath test_path(FPL("/mount"));
 
   // Should handle isolated file system.
   EXPECT_TRUE(isolated_context()->HandlesFileSystemMountType(
diff --git a/webkit/fileapi/isolated_file_util.cc b/webkit/fileapi/isolated_file_util.cc
index efe485eff8017f..66abe551f4c4a5 100644
--- a/webkit/fileapi/isolated_file_util.cc
+++ b/webkit/fileapi/isolated_file_util.cc
@@ -34,10 +34,10 @@ class SetFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
   virtual ~SetFileEnumerator() {}
 
   // AbstractFileEnumerator overrides.
-  virtual FilePath Next() OVERRIDE {
+  virtual base::FilePath Next() OVERRIDE {
     if (file_iter_ == files_.end())
-      return FilePath();
-    FilePath platform_file = (file_iter_++)->path;
+      return base::FilePath();
+    base::FilePath platform_file = (file_iter_++)->path;
     NativeFileUtil::GetFileInfo(platform_file, &file_info_);
     return platform_file;
   }
@@ -65,7 +65,7 @@ class RecursiveSetFileEnumerator
   virtual ~RecursiveSetFileEnumerator() {}
 
   // AbstractFileEnumerator overrides.
-  virtual FilePath Next() OVERRIDE;
+  virtual base::FilePath Next() OVERRIDE;
   virtual int64 Size() OVERRIDE {
     DCHECK(current_enumerator_.get());
     return current_enumerator_->Size();
@@ -85,16 +85,16 @@ class RecursiveSetFileEnumerator
   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> current_enumerator_;
 };
 
-FilePath RecursiveSetFileEnumerator::Next() {
+base::FilePath RecursiveSetFileEnumerator::Next() {
   if (current_enumerator_.get()) {
-    FilePath path = current_enumerator_->Next();
+    base::FilePath path = current_enumerator_->Next();
     if (!path.empty())
       return path;
   }
 
   // We reached the end.
   if (file_iter_ == files_.end())
-    return FilePath();
+    return base::FilePath();
 
   // Enumerates subdirectories of the next path.
   FileInfo& next_file = *file_iter_++;
@@ -113,7 +113,7 @@ IsolatedFileUtil::IsolatedFileUtil() {}
 PlatformFileError IsolatedFileUtil::GetLocalFilePath(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
-    FilePath* local_file_path) {
+    base::FilePath* local_file_path) {
   DCHECK(local_file_path);
   DCHECK(url.is_valid());
   if (url.path().empty()) {
@@ -132,7 +132,7 @@ PlatformFileError DraggedFileUtil::GetFileInfo(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     PlatformFileInfo* file_info,
-    FilePath* platform_path) {
+    base::FilePath* platform_path) {
   DCHECK(file_info);
   std::string filesystem_id;
   DCHECK(url.is_valid());
@@ -149,7 +149,7 @@ PlatformFileError DraggedFileUtil::GetFileInfo(
   }
   base::PlatformFileError error =
       NativeFileUtil::GetFileInfo(url.path(), file_info);
-  if (file_util::IsLink(url.path()) && !FilePath().IsParent(url.path())) {
+  if (file_util::IsLink(url.path()) && !base::FilePath().IsParent(url.path())) {
     // Don't follow symlinks unless it's the one that are selected by the user.
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
   }
diff --git a/webkit/fileapi/isolated_file_util.h b/webkit/fileapi/isolated_file_util.h
index e2f65ee671f4ea..9f3ae901201583 100644
--- a/webkit/fileapi/isolated_file_util.h
+++ b/webkit/fileapi/isolated_file_util.h
@@ -22,7 +22,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE IsolatedFileUtil : public LocalFileUtil {
   virtual base::PlatformFileError GetLocalFilePath(
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
-      FilePath* local_file_path) OVERRIDE;
+      base::FilePath* local_file_path) OVERRIDE;
 };
 
 // Dragged file system is a specialized IsolatedFileUtil where read access to
@@ -38,7 +38,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE DraggedFileUtil : public IsolatedFileUtil {
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path) OVERRIDE;
+      base::FilePath* platform_path) OVERRIDE;
   virtual scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
       FileSystemOperationContext* context,
       const FileSystemURL& root_url,
diff --git a/webkit/fileapi/isolated_file_util_unittest.cc b/webkit/fileapi/isolated_file_util_unittest.cc
index 06c1a34a3c7291..4652372b9e9279 100644
--- a/webkit/fileapi/isolated_file_util_unittest.cc
+++ b/webkit/fileapi/isolated_file_util_unittest.cc
@@ -39,16 +39,16 @@ namespace {
 // Random root paths in which we create each file/directory of the
 // RegularTestCases (so that we can simulate a drop with files/directories
 // from multiple directories).
-static const FilePath::CharType* kRootPaths[] = {
+static const base::FilePath::CharType* kRootPaths[] = {
   FILE_PATH_LITERAL("a"),
   FILE_PATH_LITERAL("b/c"),
   FILE_PATH_LITERAL("etc"),
 };
 
-FilePath GetTopLevelPath(const FilePath& path) {
-  std::vector<FilePath::StringType> components;
+base::FilePath GetTopLevelPath(const base::FilePath& path) {
+  std::vector<base::FilePath::StringType> components;
   path.GetComponents(&components);
-  return FilePath(components[0]);
+  return base::FilePath(components[0]);
 }
 
 bool IsDirectoryEmpty(FileSystemOperationContext* context,
@@ -100,7 +100,7 @@ class IsolatedFileUtilTest : public testing::Test {
   IsolatedContext* isolated_context() const {
     return IsolatedContext::GetInstance();
   }
-  const FilePath& root_path() const {
+  const base::FilePath& root_path() const {
     return data_dir_.path();
   }
   FileSystemContext* file_system_context() const {
@@ -112,20 +112,20 @@ class IsolatedFileUtilTest : public testing::Test {
   }
   std::string filesystem_id() const { return filesystem_id_; }
 
-  FilePath GetTestCasePlatformPath(const FilePath::StringType& path) {
-    return toplevel_root_map_[GetTopLevelPath(FilePath(path))].Append(path).
+  base::FilePath GetTestCasePlatformPath(const base::FilePath::StringType& path) {
+    return toplevel_root_map_[GetTopLevelPath(base::FilePath(path))].Append(path).
         NormalizePathSeparators();
   }
 
-  FilePath GetTestCaseLocalPath(const FilePath& path) {
-    FilePath relative;
+  base::FilePath GetTestCaseLocalPath(const base::FilePath& path) {
+    base::FilePath relative;
     if (data_dir_.path().AppendRelativePath(path, &relative))
       return relative;
     return path;
   }
 
-  FileSystemURL GetFileSystemURL(const FilePath& path) const {
-    FilePath virtual_path = isolated_context()->CreateVirtualRootPath(
+  FileSystemURL GetFileSystemURL(const base::FilePath& path) const {
+    base::FilePath virtual_path = isolated_context()->CreateVirtualRootPath(
         filesystem_id()).Append(path);
     return file_system_context_->CreateCrackedFileSystemURL(
         GURL("http://example.com"),
@@ -133,7 +133,7 @@ class IsolatedFileUtilTest : public testing::Test {
         virtual_path);
   }
 
-  FileSystemURL GetOtherFileSystemURL(const FilePath& path) {
+  FileSystemURL GetOtherFileSystemURL(const base::FilePath& path) {
     return other_file_util_helper_.CreateURL(GetTestCaseLocalPath(path));
   }
 
@@ -145,7 +145,7 @@ class IsolatedFileUtilTest : public testing::Test {
 
     // Get the file info for url1.
     base::PlatformFileInfo info1;
-    FilePath platform_path1;
+    base::FilePath platform_path1;
     context.reset(new FileSystemOperationContext(file_system_context()));
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util1->GetFileInfo(context.get(), url1,
@@ -153,7 +153,7 @@ class IsolatedFileUtilTest : public testing::Test {
 
     // Get the file info for url2.
     base::PlatformFileInfo info2;
-    FilePath platform_path2;
+    base::FilePath platform_path2;
     context.reset(new FileSystemOperationContext(file_system_context()));
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util2->GetFileInfo(context.get(), url2,
@@ -176,20 +176,20 @@ class IsolatedFileUtilTest : public testing::Test {
                                         const FileSystemURL& root1,
                                         const FileSystemURL& root2) {
     scoped_ptr<FileSystemOperationContext> context;
-    FilePath root_path1 = root1.path();
-    FilePath root_path2 = root2.path();
+    base::FilePath root_path1 = root1.path();
+    base::FilePath root_path2 = root2.path();
 
     context.reset(new FileSystemOperationContext(file_system_context()));
     scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> file_enum1 =
         file_util1->CreateFileEnumerator(context.get(), root1,
                                          true /* recursive */);
 
-    FilePath current;
-    std::set<FilePath> file_set1;
+    base::FilePath current;
+    std::set<base::FilePath> file_set1;
     while (!(current = file_enum1->Next()).empty()) {
       if (file_enum1->IsDirectory())
         continue;
-      FilePath relative;
+      base::FilePath relative;
       root_path1.AppendRelativePath(current, &relative);
       file_set1.insert(relative);
     }
@@ -200,7 +200,7 @@ class IsolatedFileUtilTest : public testing::Test {
                                          true /* recursive */);
 
     while (!(current = file_enum2->Next()).empty()) {
-      FilePath relative;
+      base::FilePath relative;
       root_path2.AppendRelativePath(current, &relative);
       FileSystemURL url1 = root1.WithPath(root_path1.Append(relative));
       FileSystemURL url2 = root2.WithPath(root_path2.Append(relative));
@@ -229,13 +229,13 @@ class IsolatedFileUtilTest : public testing::Test {
     IsolatedContext::FileInfoSet toplevels;
     for (size_t i = 0; i < test::kRegularTestCaseSize; ++i) {
       const test::TestCaseRecord& test_case = test::kRegularTestCases[i];
-      FilePath path(test_case.path);
-      FilePath toplevel = GetTopLevelPath(path);
+      base::FilePath path(test_case.path);
+      base::FilePath toplevel = GetTopLevelPath(path);
 
       // We create the test case files under one of the kRootPaths
       // to simulate a drop with multiple directories.
       if (toplevel_root_map_.find(toplevel) == toplevel_root_map_.end()) {
-        FilePath root = root_path().Append(
+        base::FilePath root = root_path().Append(
             kRootPaths[(root_path_index++) % arraysize(kRootPaths)]);
         toplevel_root_map_[toplevel] = root;
         toplevels.AddPath(root.Append(path), NULL);
@@ -253,7 +253,7 @@ class IsolatedFileUtilTest : public testing::Test {
   MessageLoop message_loop_;
   std::string filesystem_id_;
   scoped_refptr<FileSystemContext> file_system_context_;
-  std::map<FilePath, FilePath> toplevel_root_map_;
+  std::map<base::FilePath, base::FilePath> toplevel_root_map_;
   scoped_ptr<IsolatedFileUtil> file_util_;
   LocalFileSystemTestOriginHelper other_file_util_helper_;
   DISALLOW_COPY_AND_ASSIGN(IsolatedFileUtilTest);
@@ -264,13 +264,13 @@ TEST_F(IsolatedFileUtilTest, BasicTest) {
     SCOPED_TRACE(testing::Message() << "Testing RegularTestCases " << i);
     const test::TestCaseRecord& test_case = test::kRegularTestCases[i];
 
-    FileSystemURL url = GetFileSystemURL(FilePath(test_case.path));
+    FileSystemURL url = GetFileSystemURL(base::FilePath(test_case.path));
 
     // See if we can query the file info via the isolated FileUtil.
     // (This should succeed since we have registered all the top-level
     // entries of the test cases in SetUp())
     base::PlatformFileInfo info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     FileSystemOperationContext context(file_system_context());
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util()->GetFileInfo(&context, url, &info, &platform_path));
@@ -312,7 +312,7 @@ TEST_F(IsolatedFileUtilTest, UnregisteredPathsTest) {
   for (size_t i = 0; i < arraysize(kUnregisteredCases); ++i) {
     SCOPED_TRACE(testing::Message() << "Creating kUnregisteredCases " << i);
     const test::TestCaseRecord& test_case = kUnregisteredCases[i];
-    FileSystemURL url = GetFileSystemURL(FilePath(test_case.path));
+    FileSystemURL url = GetFileSystemURL(base::FilePath(test_case.path));
 
     // We should not be able to get the valid URL for unregistered files.
     ASSERT_FALSE(url.is_valid());
@@ -336,13 +336,13 @@ TEST_F(IsolatedFileUtilTest, ReadDirectoryTest) {
                  << ": " << test_case.path);
 
     // Read entries in the directory to construct the expected results map.
-    typedef std::map<FilePath::StringType, base::FileUtilProxy::Entry> EntryMap;
+    typedef std::map<base::FilePath::StringType, base::FileUtilProxy::Entry> EntryMap;
     EntryMap expected_entry_map;
 
     FileEnumerator file_enum(
         GetTestCasePlatformPath(test_case.path), false /* not recursive */,
         FileEnumerator::FILES | FileEnumerator::DIRECTORIES);
-    FilePath current;
+    base::FilePath current;
     while (!(current = file_enum.Next()).empty()) {
       FileEnumerator::FindInfo file_info;
       file_enum.GetFindInfo(&file_info);
@@ -355,7 +355,7 @@ TEST_F(IsolatedFileUtilTest, ReadDirectoryTest) {
     }
 
     // Perform ReadDirectory in the isolated filesystem.
-    FileSystemURL url = GetFileSystemURL(FilePath(test_case.path));
+    FileSystemURL url = GetFileSystemURL(base::FilePath(test_case.path));
     std::vector<base::FileUtilProxy::Entry> entries;
     FileSystemOperationContext context(file_system_context());
     ASSERT_EQ(base::PLATFORM_FILE_OK,
@@ -379,11 +379,11 @@ TEST_F(IsolatedFileUtilTest, ReadDirectoryTest) {
 TEST_F(IsolatedFileUtilTest, GetLocalFilePathTest) {
   for (size_t i = 0; i < test::kRegularTestCaseSize; ++i) {
     const test::TestCaseRecord& test_case = test::kRegularTestCases[i];
-    FileSystemURL url = GetFileSystemURL(FilePath(test_case.path));
+    FileSystemURL url = GetFileSystemURL(base::FilePath(test_case.path));
 
     FileSystemOperationContext context(file_system_context());
 
-    FilePath local_file_path;
+    base::FilePath local_file_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK,
               file_util()->GetLocalFilePath(&context, url, &local_file_path));
     EXPECT_EQ(GetTestCasePlatformPath(test_case.path).value(),
@@ -394,12 +394,12 @@ TEST_F(IsolatedFileUtilTest, GetLocalFilePathTest) {
 TEST_F(IsolatedFileUtilTest, CopyOutFileTest) {
   scoped_ptr<FileSystemOperationContext> context(
       new FileSystemOperationContext(file_system_context()));
-  FileSystemURL root_url = GetFileSystemURL(FilePath());
+  FileSystemURL root_url = GetFileSystemURL(base::FilePath());
   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> file_enum(
       file_util()->CreateFileEnumerator(context.get(),
                                         root_url,
                                         true /* recursive */));
-  FilePath current;
+  base::FilePath current;
   while (!(current = file_enum->Next()).empty()) {
     if (file_enum->IsDirectory())
       continue;
@@ -434,12 +434,12 @@ TEST_F(IsolatedFileUtilTest, CopyOutFileTest) {
 TEST_F(IsolatedFileUtilTest, CopyOutDirectoryTest) {
   scoped_ptr<FileSystemOperationContext> context(
       new FileSystemOperationContext(file_system_context()));
-  FileSystemURL root_url = GetFileSystemURL(FilePath());
+  FileSystemURL root_url = GetFileSystemURL(base::FilePath());
   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> file_enum(
       file_util()->CreateFileEnumerator(context.get(),
                                         root_url,
                                         false /* recursive */));
-  FilePath current;
+  base::FilePath current;
   while (!(current = file_enum->Next()).empty()) {
     if (!file_enum->IsDirectory())
       continue;
@@ -477,7 +477,7 @@ TEST_F(IsolatedFileUtilTest, TouchTest) {
     if (test_case.is_directory)
       continue;
     SCOPED_TRACE(testing::Message() << test_case.path);
-    FileSystemURL url = GetFileSystemURL(FilePath(test_case.path));
+    FileSystemURL url = GetFileSystemURL(base::FilePath(test_case.path));
 
     base::Time last_access_time = base::Time::FromTimeT(1000);
     base::Time last_modified_time = base::Time::FromTimeT(2000);
@@ -489,7 +489,7 @@ TEST_F(IsolatedFileUtilTest, TouchTest) {
 
     // Verification.
     base::PlatformFileInfo info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util()->GetFileInfo(GetOperationContext().get(), url,
                                        &info, &platform_path));
@@ -505,11 +505,11 @@ TEST_F(IsolatedFileUtilTest, TruncateTest) {
       continue;
 
     SCOPED_TRACE(testing::Message() << test_case.path);
-    FileSystemURL url = GetFileSystemURL(FilePath(test_case.path));
+    FileSystemURL url = GetFileSystemURL(base::FilePath(test_case.path));
 
     // Truncate to 0.
     base::PlatformFileInfo info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK,
               file_util()->Truncate(GetOperationContext().get(), url, 0));
     ASSERT_EQ(base::PLATFORM_FILE_OK,
diff --git a/webkit/fileapi/isolated_mount_point_provider.cc b/webkit/fileapi/isolated_mount_point_provider.cc
index f21909c36df252..160a71c189aeb5 100644
--- a/webkit/fileapi/isolated_mount_point_provider.cc
+++ b/webkit/fileapi/isolated_mount_point_provider.cc
@@ -35,7 +35,7 @@
 namespace fileapi {
 
 IsolatedMountPointProvider::IsolatedMountPointProvider(
-    const FilePath& profile_path)
+    const base::FilePath& profile_path)
     : profile_path_(profile_path),
       media_path_filter_(new MediaPathFilter()),
       isolated_file_util_(new AsyncFileUtilAdapter(new IsolatedFileUtil())),
@@ -64,12 +64,12 @@ void IsolatedMountPointProvider::ValidateFileSystemRoot(
       base::Bind(callback, base::PLATFORM_FILE_ERROR_SECURITY));
 }
 
-FilePath IsolatedMountPointProvider::GetFileSystemRootPathOnFileThread(
+base::FilePath IsolatedMountPointProvider::GetFileSystemRootPathOnFileThread(
     const FileSystemURL& url,
     bool create) {
   // This is not supposed to be used.
   NOTREACHED();
-  return FilePath();
+  return base::FilePath();
 }
 
 bool IsolatedMountPointProvider::IsAccessAllowed(const FileSystemURL& url) {
@@ -77,7 +77,7 @@ bool IsolatedMountPointProvider::IsAccessAllowed(const FileSystemURL& url) {
 }
 
 bool IsolatedMountPointProvider::IsRestrictedFileName(
-    const FilePath& filename) const {
+    const base::FilePath& filename) const {
   // TODO(kinuko): We need to check platform-specific restricted file names
   // before we actually start allowing file creation in isolated file systems.
   return false;
diff --git a/webkit/fileapi/isolated_mount_point_provider.h b/webkit/fileapi/isolated_mount_point_provider.h
index 5c89f116a90549..64f82a665e656d 100644
--- a/webkit/fileapi/isolated_mount_point_provider.h
+++ b/webkit/fileapi/isolated_mount_point_provider.h
@@ -17,7 +17,7 @@ class MediaPathFilter;
 
 class IsolatedMountPointProvider : public FileSystemMountPointProvider {
  public:
-  explicit IsolatedMountPointProvider(const FilePath& profile_path);
+  explicit IsolatedMountPointProvider(const base::FilePath& profile_path);
   virtual ~IsolatedMountPointProvider();
 
   // FileSystemMountPointProvider implementation.
@@ -26,11 +26,11 @@ class IsolatedMountPointProvider : public FileSystemMountPointProvider {
       FileSystemType type,
       bool create,
       const ValidateFileSystemCallback& callback) OVERRIDE;
-  virtual FilePath GetFileSystemRootPathOnFileThread(
+  virtual base::FilePath GetFileSystemRootPathOnFileThread(
       const FileSystemURL& url,
       bool create) OVERRIDE;
   virtual bool IsAccessAllowed(const FileSystemURL& url) OVERRIDE;
-  virtual bool IsRestrictedFileName(const FilePath& filename) const OVERRIDE;
+  virtual bool IsRestrictedFileName(const base::FilePath& filename) const OVERRIDE;
   virtual FileSystemFileUtil* GetFileUtil(FileSystemType type) OVERRIDE;
   virtual AsyncFileUtil* GetAsyncFileUtil(FileSystemType type) OVERRIDE;
   virtual FilePermissionPolicy GetPermissionPolicy(
@@ -58,7 +58,7 @@ class IsolatedMountPointProvider : public FileSystemMountPointProvider {
 
  private:
   // Store the profile path. We need this to create temporary snapshot files.
-  const FilePath profile_path_;
+  const base::FilePath profile_path_;
 
   scoped_ptr<MediaPathFilter> media_path_filter_;
 
diff --git a/webkit/fileapi/local_file_stream_writer.cc b/webkit/fileapi/local_file_stream_writer.cc
index f3679f9e1ca73b..e17784e0e7e496 100644
--- a/webkit/fileapi/local_file_stream_writer.cc
+++ b/webkit/fileapi/local_file_stream_writer.cc
@@ -20,7 +20,7 @@ const int kOpenFlagsForWrite = base::PLATFORM_FILE_OPEN |
 
 }  // namespace
 
-LocalFileStreamWriter::LocalFileStreamWriter(const FilePath& file_path,
+LocalFileStreamWriter::LocalFileStreamWriter(const base::FilePath& file_path,
                                              int64 initial_offset)
     : file_path_(file_path),
       initial_offset_(initial_offset),
diff --git a/webkit/fileapi/local_file_stream_writer.h b/webkit/fileapi/local_file_stream_writer.h
index e23b476b71fb8c..a6d15f930ca501 100644
--- a/webkit/fileapi/local_file_stream_writer.h
+++ b/webkit/fileapi/local_file_stream_writer.h
@@ -28,7 +28,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE LocalFileStreamWriter
  public:
   // Create a writer for the existing file in the path |file_path| starting from
   // |initial_offset|.
-  LocalFileStreamWriter(const FilePath& file_path, int64 initial_offset);
+  LocalFileStreamWriter(const base::FilePath& file_path, int64 initial_offset);
   virtual ~LocalFileStreamWriter();
 
   // FileStreamWriter overrides.
@@ -72,7 +72,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE LocalFileStreamWriter
   bool CancelIfRequested();
 
   // Initialization parameters.
-  const FilePath file_path_;
+  const base::FilePath file_path_;
   const int64 initial_offset_;
 
   // Current states of the operation.
diff --git a/webkit/fileapi/local_file_stream_writer_unittest.cc b/webkit/fileapi/local_file_stream_writer_unittest.cc
index 3fda6d62324a20..d67a7daba96367 100644
--- a/webkit/fileapi/local_file_stream_writer_unittest.cc
+++ b/webkit/fileapi/local_file_stream_writer_unittest.cc
@@ -29,7 +29,7 @@ class LocalFileStreamWriterTest : public testing::Test {
   }
 
  protected:
-  FilePath Path(const std::string& name) {
+  base::FilePath Path(const std::string& name) {
     return temp_dir_.path().AppendASCII(name);
   }
 
@@ -52,15 +52,15 @@ class LocalFileStreamWriterTest : public testing::Test {
     return net::OK;
   }
 
-  std::string GetFileContent(const FilePath& path) {
+  std::string GetFileContent(const base::FilePath& path) {
     std::string content;
     file_util::ReadFileToString(path, &content);
     return content;
   }
 
-  FilePath CreateFileWithContent(const std::string& name,
+  base::FilePath CreateFileWithContent(const std::string& name,
                                  const std::string& data) {
-    FilePath path = Path(name);
+    base::FilePath path = Path(name);
     file_util::WriteFile(path, data.c_str(), data.size());
     return path;
   }
@@ -77,7 +77,7 @@ void NeverCalled(int unused) {
 }  // namespace
 
 TEST_F(LocalFileStreamWriterTest, Write) {
-  FilePath path = CreateFileWithContent("file_a", "");
+  base::FilePath path = CreateFileWithContent("file_a", "");
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 0));
   EXPECT_EQ(net::OK, WriteStringToWriter(writer.get(), "foo"));
   EXPECT_EQ(net::OK, WriteStringToWriter(writer.get(), "bar"));
@@ -88,7 +88,7 @@ TEST_F(LocalFileStreamWriterTest, Write) {
 }
 
 TEST_F(LocalFileStreamWriterTest, WriteMiddle) {
-  FilePath path = CreateFileWithContent("file_a", "foobar");
+  base::FilePath path = CreateFileWithContent("file_a", "foobar");
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 2));
   EXPECT_EQ(net::OK, WriteStringToWriter(writer.get(), "xxx"));
   writer.reset();
@@ -98,7 +98,7 @@ TEST_F(LocalFileStreamWriterTest, WriteMiddle) {
 }
 
 TEST_F(LocalFileStreamWriterTest, WriteEnd) {
-  FilePath path = CreateFileWithContent("file_a", "foobar");
+  base::FilePath path = CreateFileWithContent("file_a", "foobar");
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 6));
   EXPECT_EQ(net::OK, WriteStringToWriter(writer.get(), "xxx"));
   writer.reset();
@@ -108,7 +108,7 @@ TEST_F(LocalFileStreamWriterTest, WriteEnd) {
 }
 
 TEST_F(LocalFileStreamWriterTest, WriteFailForNonexistingFile) {
-  FilePath path = Path("file_a");
+  base::FilePath path = Path("file_a");
   ASSERT_FALSE(file_util::PathExists(path));
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 0));
   EXPECT_EQ(net::ERR_FILE_NOT_FOUND, WriteStringToWriter(writer.get(), "foo"));
@@ -118,7 +118,7 @@ TEST_F(LocalFileStreamWriterTest, WriteFailForNonexistingFile) {
 }
 
 TEST_F(LocalFileStreamWriterTest, CancelBeforeOperation) {
-  FilePath path = Path("file_a");
+  base::FilePath path = Path("file_a");
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 0));
   // Cancel immediately fails when there's no in-flight operation.
   int cancel_result = writer->Cancel(base::Bind(&NeverCalled));
@@ -126,7 +126,7 @@ TEST_F(LocalFileStreamWriterTest, CancelBeforeOperation) {
 }
 
 TEST_F(LocalFileStreamWriterTest, CancelAfterFinishedOperation) {
-  FilePath path = CreateFileWithContent("file_a", "");
+  base::FilePath path = CreateFileWithContent("file_a", "");
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 0));
   EXPECT_EQ(net::OK, WriteStringToWriter(writer.get(), "foo"));
 
@@ -142,7 +142,7 @@ TEST_F(LocalFileStreamWriterTest, CancelAfterFinishedOperation) {
 }
 
 TEST_F(LocalFileStreamWriterTest, CancelWrite) {
-  FilePath path = CreateFileWithContent("file_a", "foobar");
+  base::FilePath path = CreateFileWithContent("file_a", "foobar");
   scoped_ptr<LocalFileStreamWriter> writer(new LocalFileStreamWriter(path, 0));
 
   scoped_refptr<net::StringIOBuffer> buffer(new net::StringIOBuffer("xxx"));
diff --git a/webkit/fileapi/local_file_system_operation.cc b/webkit/fileapi/local_file_system_operation.cc
index edf26b0088bd8a..4cda1f80d8b943 100644
--- a/webkit/fileapi/local_file_system_operation.cc
+++ b/webkit/fileapi/local_file_system_operation.cc
@@ -193,7 +193,7 @@ void LocalFileSystemOperation::GetMetadata(
 
   base::PlatformFileError result = SetUp(url, SETUP_FOR_READ);
   if (result != base::PLATFORM_FILE_OK) {
-    callback.Run(result, base::PlatformFileInfo(), FilePath());
+    callback.Run(result, base::PlatformFileInfo(), base::FilePath());
     delete this;
     return;
   }
@@ -372,7 +372,7 @@ LocalFileSystemOperation::AsLocalFileSystemOperation() {
 }
 
 void LocalFileSystemOperation::SyncGetPlatformPath(const FileSystemURL& url,
-                                                   FilePath* platform_path) {
+                                                   base::FilePath* platform_path) {
   DCHECK(SetPendingOperationType(kOperationGetLocalPath));
 
   base::PlatformFileError result = SetUp(url, SETUP_FOR_READ);
@@ -396,7 +396,7 @@ void LocalFileSystemOperation::CreateSnapshotFile(
 
   base::PlatformFileError result = SetUp(url, SETUP_FOR_READ);
   if (result != base::PLATFORM_FILE_OK) {
-    callback.Run(result, base::PlatformFileInfo(), FilePath(), NULL);
+    callback.Run(result, base::PlatformFileInfo(), base::FilePath(), NULL);
     delete this;
     return;
   }
@@ -408,7 +408,7 @@ void LocalFileSystemOperation::CreateSnapshotFile(
 }
 
 void LocalFileSystemOperation::CopyInForeignFile(
-    const FilePath& src_local_disk_file_path,
+    const base::FilePath& src_local_disk_file_path,
     const FileSystemURL& dest_url,
     const StatusCallback& callback) {
   DCHECK(SetPendingOperationType(kOperationCopyInForeignFile));
@@ -666,7 +666,7 @@ void LocalFileSystemOperation::DoMoveFileLocal(
 }
 
 void LocalFileSystemOperation::DoCopyInForeignFile(
-    const FilePath& src_local_disk_file_path,
+    const base::FilePath& src_local_disk_file_path,
     const FileSystemURL& dest_url,
     const StatusCallback& callback) {
   async_file_util_->CopyInForeignFile(
@@ -737,7 +737,7 @@ void LocalFileSystemOperation::DidDirectoryExists(
     const StatusCallback& callback,
     base::PlatformFileError rv,
     const base::PlatformFileInfo& file_info,
-    const FilePath& unused) {
+    const base::FilePath& unused) {
   if (rv == base::PLATFORM_FILE_OK && !file_info.is_directory)
     rv = base::PLATFORM_FILE_ERROR_NOT_A_DIRECTORY;
   callback.Run(rv);
@@ -747,7 +747,7 @@ void LocalFileSystemOperation::DidFileExists(
     const StatusCallback& callback,
     base::PlatformFileError rv,
     const base::PlatformFileInfo& file_info,
-    const FilePath& unused) {
+    const base::FilePath& unused) {
   if (rv == base::PLATFORM_FILE_OK && file_info.is_directory)
     rv = base::PLATFORM_FILE_ERROR_NOT_A_FILE;
   callback.Run(rv);
@@ -757,7 +757,7 @@ void LocalFileSystemOperation::DidGetMetadata(
     const GetMetadataCallback& callback,
     base::PlatformFileError rv,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   callback.Run(rv, file_info, platform_path);
 }
 
@@ -812,7 +812,7 @@ void LocalFileSystemOperation::DidCreateSnapshotFile(
     const SnapshotFileCallback& callback,
     base::PlatformFileError result,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path,
+    const base::FilePath& platform_path,
     SnapshotFilePolicy snapshot_policy) {
   scoped_refptr<ShareableFileReference> file_ref;
   if (result == base::PLATFORM_FILE_OK &&
diff --git a/webkit/fileapi/local_file_system_operation.h b/webkit/fileapi/local_file_system_operation.h
index cd828d849765d9..73ee457e1b0a12 100644
--- a/webkit/fileapi/local_file_system_operation.h
+++ b/webkit/fileapi/local_file_system_operation.h
@@ -91,7 +91,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   // - PLATFORM_FILE_ERROR_FAILED if |dest_url| does not exist and
   //   its parent path is a file.
   //
-  void CopyInForeignFile(const FilePath& src_local_disk_path,
+  void CopyInForeignFile(const base::FilePath& src_local_disk_path,
                          const FileSystemURL& dest_url,
                          const StatusCallback& callback);
 
@@ -149,7 +149,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
                      const StatusCallback& callback);
 
   // Synchronously gets the platform path for the given |url|.
-  void SyncGetPlatformPath(const FileSystemURL& url, FilePath* platform_path);
+  void SyncGetPlatformPath(const FileSystemURL& url, base::FilePath* platform_path);
 
  private:
   class ScopedUpdateNotifier;
@@ -235,7 +235,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   void DoMoveFileLocal(const FileSystemURL& src,
                        const FileSystemURL& dest,
                        const StatusCallback& callback);
-  void DoCopyInForeignFile(const FilePath& src_local_disk_file_path,
+  void DoCopyInForeignFile(const base::FilePath& src_local_disk_file_path,
                            const FileSystemURL& dest,
                            const StatusCallback& callback);
   void DoTruncate(const FileSystemURL& url,
@@ -264,15 +264,15 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
   void DidDirectoryExists(const StatusCallback& callback,
                           base::PlatformFileError rv,
                           const base::PlatformFileInfo& file_info,
-                          const FilePath& unused);
+                          const base::FilePath& unused);
   void DidFileExists(const StatusCallback& callback,
                      base::PlatformFileError rv,
                      const base::PlatformFileInfo& file_info,
-                     const FilePath& unused);
+                     const base::FilePath& unused);
   void DidGetMetadata(const GetMetadataCallback& callback,
                       base::PlatformFileError rv,
                       const base::PlatformFileInfo& file_info,
-                      const FilePath& platform_path);
+                      const base::FilePath& platform_path);
   void DidReadDirectory(const ReadDirectoryCallback& callback,
                         base::PlatformFileError rv,
                         const std::vector<base::FileUtilProxy::Entry>& entries,
@@ -291,7 +291,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSystemOperation
       const SnapshotFileCallback& callback,
       base::PlatformFileError rv,
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       SnapshotFilePolicy snapshot_policy);
 
   // Checks the validity of a given |url| and populates |file_util| for |mode|.
diff --git a/webkit/fileapi/local_file_system_operation_unittest.cc b/webkit/fileapi/local_file_system_operation_unittest.cc
index c49e2b2adf628b..37b76a5138c725 100644
--- a/webkit/fileapi/local_file_system_operation_unittest.cc
+++ b/webkit/fileapi/local_file_system_operation_unittest.cc
@@ -58,7 +58,7 @@ class LocalFileSystemOperationTest
 
   int status() const { return status_; }
   const base::PlatformFileInfo& info() const { return info_; }
-  const FilePath& path() const { return path_; }
+  const base::FilePath& path() const { return path_; }
   const std::vector<base::FileUtilProxy::Entry>& entries() const {
     return entries_;
   }
@@ -101,32 +101,32 @@ class LocalFileSystemOperationTest
     return context;
   }
 
-  FileSystemURL URLForPath(const FilePath& path) const {
+  FileSystemURL URLForPath(const base::FilePath& path) const {
     return test_helper_.CreateURL(path);
   }
 
-  FilePath PlatformPath(const FilePath& virtual_path) {
+  base::FilePath PlatformPath(const base::FilePath& virtual_path) {
     return test_helper_.GetLocalPath(virtual_path);
   }
 
-  bool FileExists(const FilePath& virtual_path) {
+  bool FileExists(const base::FilePath& virtual_path) {
     FileSystemURL url = test_helper_.CreateURL(virtual_path);
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     scoped_ptr<FileSystemOperationContext> context(NewContext());
     base::PlatformFileError error = file_util()->GetFileInfo(
         context.get(), url, &file_info, &platform_path);
     return error == base::PLATFORM_FILE_OK && !file_info.is_directory;
   }
 
-  bool DirectoryExists(const FilePath& virtual_path) {
+  bool DirectoryExists(const base::FilePath& virtual_path) {
     FileSystemURL url = test_helper_.CreateURL(virtual_path);
     scoped_ptr<FileSystemOperationContext> context(NewContext());
     return FileUtilHelper::DirectoryExists(context.get(), file_util(), url);
   }
 
-  FilePath CreateUniqueFileInDir(const FilePath& virtual_dir_path) {
-    FilePath file_name = FilePath::FromUTF8Unsafe(
+  base::FilePath CreateUniqueFileInDir(const base::FilePath& virtual_dir_path) {
+    base::FilePath file_name = base::FilePath::FromUTF8Unsafe(
         "tmpfile-" + base::IntToString(next_unique_path_suffix_++));
     FileSystemURL url = test_helper_.CreateURL(
         virtual_dir_path.Append(file_name));
@@ -139,8 +139,8 @@ class LocalFileSystemOperationTest
     return url.path();
   }
 
-  FilePath CreateUniqueDirInDir(const FilePath& virtual_dir_path) {
-    FilePath dir_name = FilePath::FromUTF8Unsafe(
+  base::FilePath CreateUniqueDirInDir(const base::FilePath& virtual_dir_path) {
+    base::FilePath dir_name = base::FilePath::FromUTF8Unsafe(
         "tmpdir-" + base::IntToString(next_unique_path_suffix_++));
     FileSystemURL url = test_helper_.CreateURL(
         virtual_dir_path.Append(dir_name));
@@ -151,8 +151,8 @@ class LocalFileSystemOperationTest
     return url.path();
   }
 
-  FilePath CreateUniqueDir() {
-    return CreateUniqueDirInDir(FilePath());
+  base::FilePath CreateUniqueDir() {
+    return CreateUniqueDirInDir(base::FilePath());
   }
 
   LocalFileSystemTestOriginHelper test_helper_;
@@ -192,7 +192,7 @@ class LocalFileSystemOperationTest
 
   void DidGetMetadata(base::PlatformFileError status,
                       const base::PlatformFileInfo& info,
-                      const FilePath& platform_path) {
+                      const base::FilePath& platform_path) {
     info_ = info;
     path_ = platform_path;
     status_ = status;
@@ -201,7 +201,7 @@ class LocalFileSystemOperationTest
   void DidCreateSnapshotFile(
       base::PlatformFileError status,
       const base::PlatformFileInfo& info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       const scoped_refptr<ShareableFileReference>& shareable_file_ref) {
     info_ = info;
     path_ = platform_path;
@@ -236,8 +236,8 @@ class LocalFileSystemOperationTest
     ASSERT_EQ(quota::kQuotaStatusOk, status);
   }
 
-  void GenerateUniquePathInDir(const FilePath& dir,
-                               FilePath* file_path,
+  void GenerateUniquePathInDir(const base::FilePath& dir,
+                               base::FilePath* file_path,
                                int64* path_cost) {
     int64 base_usage;
     GetUsageAndQuota(&base_usage, NULL);
@@ -272,7 +272,7 @@ class LocalFileSystemOperationTest
   // For post-operation status.
   int status_;
   base::PlatformFileInfo info_;
-  FilePath path_;
+  base::FilePath path_;
   std::vector<base::FileUtilProxy::Entry> entries_;
   scoped_refptr<ShareableFileReference> shareable_file_ref_;
 
@@ -290,7 +290,7 @@ class LocalFileSystemOperationTest
 };
 
 void LocalFileSystemOperationTest::SetUp() {
-  FilePath base_dir = base_.path().AppendASCII("filesystem");
+  base::FilePath base_dir = base_.path().AppendASCII("filesystem");
   quota_manager_ = new quota::MockQuotaManager(
       false /* is_incognito */, base_dir,
       base::MessageLoopProxy::current(),
@@ -319,8 +319,8 @@ LocalFileSystemOperation* LocalFileSystemOperationTest::operation() {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveFailureSrcDoesntExist) {
-  FileSystemURL src(URLForPath(FilePath(FILE_PATH_LITERAL("a"))));
-  FileSystemURL dest(URLForPath(FilePath(FILE_PATH_LITERAL("b"))));
+  FileSystemURL src(URLForPath(base::FilePath(FILE_PATH_LITERAL("a"))));
+  FileSystemURL dest(URLForPath(base::FilePath(FILE_PATH_LITERAL("b"))));
   change_observer()->ResetCount();
   operation()->Move(src, dest, RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -329,8 +329,8 @@ TEST_F(LocalFileSystemOperationTest, TestMoveFailureSrcDoesntExist) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveFailureContainsPath) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDirInDir(src_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDirInDir(src_dir_path));
   operation()->Move(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -340,9 +340,9 @@ TEST_F(LocalFileSystemOperationTest, TestMoveFailureContainsPath) {
 
 TEST_F(LocalFileSystemOperationTest, TestMoveFailureSrcDirExistsDestFile) {
   // Src exists and is dir. Dest is a file.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
 
   operation()->Move(URLForPath(src_dir_path), URLForPath(dest_file_path),
                     RecordStatusCallback());
@@ -354,9 +354,9 @@ TEST_F(LocalFileSystemOperationTest, TestMoveFailureSrcDirExistsDestFile) {
 TEST_F(LocalFileSystemOperationTest,
        TestMoveFailureSrcFileExistsDestNonEmptyDir) {
   // Src exists and is a directory. Dest is a non-empty directory.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath child_file_path(CreateUniqueFileInDir(dest_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath child_file_path(CreateUniqueFileInDir(dest_dir_path));
 
   operation()->Move(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -367,9 +367,9 @@ TEST_F(LocalFileSystemOperationTest,
 
 TEST_F(LocalFileSystemOperationTest, TestMoveFailureSrcFileExistsDestDir) {
   // Src exists and is a file. Dest is a directory.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
   operation()->Move(URLForPath(src_file_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -380,8 +380,8 @@ TEST_F(LocalFileSystemOperationTest, TestMoveFailureSrcFileExistsDestDir) {
 
 TEST_F(LocalFileSystemOperationTest, TestMoveFailureDestParentDoesntExist) {
   // Dest. parent path does not exist.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath nonexisting_file = FilePath(FILE_PATH_LITERAL("NonexistingDir")).
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath nonexisting_file = base::FilePath(FILE_PATH_LITERAL("NonexistingDir")).
       Append(FILE_PATH_LITERAL("NonexistingFile"));
 
   operation()->Move(URLForPath(src_dir_path), URLForPath(nonexisting_file),
@@ -392,10 +392,10 @@ TEST_F(LocalFileSystemOperationTest, TestMoveFailureDestParentDoesntExist) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcFileAndOverwrite) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
 
   operation()->Move(URLForPath(src_file_path), URLForPath(dest_file_path),
                     RecordStatusCallback());
@@ -413,10 +413,10 @@ TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcFileAndOverwrite) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcFileAndNew) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(dest_dir_path.Append(FILE_PATH_LITERAL("NewFile")));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(dest_dir_path.Append(FILE_PATH_LITERAL("NewFile")));
 
   operation()->Move(URLForPath(src_file_path), URLForPath(dest_file_path),
                     RecordStatusCallback());
@@ -430,8 +430,8 @@ TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcFileAndNew) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcDirAndOverwrite) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
   operation()->Move(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -450,9 +450,9 @@ TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcDirAndOverwrite) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcDirAndNew) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_parent_dir_path(CreateUniqueDir());
-  FilePath dest_child_dir_path(dest_parent_dir_path.
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_parent_dir_path(CreateUniqueDir());
+  base::FilePath dest_child_dir_path(dest_parent_dir_path.
       Append(FILE_PATH_LITERAL("NewDirectory")));
 
   operation()->Move(URLForPath(src_dir_path), URLForPath(dest_child_dir_path),
@@ -468,12 +468,12 @@ TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcDirAndNew) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcDirRecursive) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath child_dir_path(CreateUniqueDirInDir(src_dir_path));
-  FilePath grandchild_file_path(
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath child_dir_path(CreateUniqueDirInDir(src_dir_path));
+  base::FilePath grandchild_file_path(
       CreateUniqueFileInDir(child_dir_path));
 
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
   operation()->Move(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -493,8 +493,8 @@ TEST_F(LocalFileSystemOperationTest, TestMoveSuccessSrcDirRecursive) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopyFailureSrcDoesntExist) {
-  operation()->Copy(URLForPath(FilePath(FILE_PATH_LITERAL("a"))),
-                    URLForPath(FilePath(FILE_PATH_LITERAL("b"))),
+  operation()->Copy(URLForPath(base::FilePath(FILE_PATH_LITERAL("a"))),
+                    URLForPath(base::FilePath(FILE_PATH_LITERAL("b"))),
                     RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, status());
@@ -502,8 +502,8 @@ TEST_F(LocalFileSystemOperationTest, TestCopyFailureSrcDoesntExist) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopyFailureContainsPath) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDirInDir(src_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDirInDir(src_dir_path));
   operation()->Copy(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -513,9 +513,9 @@ TEST_F(LocalFileSystemOperationTest, TestCopyFailureContainsPath) {
 
 TEST_F(LocalFileSystemOperationTest, TestCopyFailureSrcDirExistsDestFile) {
   // Src exists and is dir. Dest is a file.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
 
   operation()->Copy(URLForPath(src_dir_path), URLForPath(dest_file_path),
                     RecordStatusCallback());
@@ -527,9 +527,9 @@ TEST_F(LocalFileSystemOperationTest, TestCopyFailureSrcDirExistsDestFile) {
 TEST_F(LocalFileSystemOperationTest,
        TestCopyFailureSrcFileExistsDestNonEmptyDir) {
   // Src exists and is a directory. Dest is a non-empty directory.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath child_file_path(CreateUniqueFileInDir(dest_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath child_file_path(CreateUniqueFileInDir(dest_dir_path));
 
   operation()->Copy(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -540,9 +540,9 @@ TEST_F(LocalFileSystemOperationTest,
 
 TEST_F(LocalFileSystemOperationTest, TestCopyFailureSrcFileExistsDestDir) {
   // Src exists and is a file. Dest is a directory.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
   operation()->Copy(URLForPath(src_file_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -553,10 +553,10 @@ TEST_F(LocalFileSystemOperationTest, TestCopyFailureSrcFileExistsDestDir) {
 
 TEST_F(LocalFileSystemOperationTest, TestCopyFailureDestParentDoesntExist) {
   // Dest. parent path does not exist.
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath nonexisting_path = FilePath(FILE_PATH_LITERAL("DontExistDir"));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath nonexisting_path = base::FilePath(FILE_PATH_LITERAL("DontExistDir"));
   file_util::EnsureEndsWithSeparator(&nonexisting_path);
-  FilePath nonexisting_file_path(nonexisting_path.Append(
+  base::FilePath nonexisting_file_path(nonexisting_path.Append(
       FILE_PATH_LITERAL("DontExistFile")));
 
   operation()->Copy(URLForPath(src_dir_path),
@@ -570,11 +570,11 @@ TEST_F(LocalFileSystemOperationTest, TestCopyFailureDestParentDoesntExist) {
 TEST_F(LocalFileSystemOperationTest, TestCopyFailureByQuota) {
   base::PlatformFileInfo info;
 
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
-  FilePath dest_file_path;
+  base::FilePath dest_file_path;
   int64 dest_path_cost;
   GenerateUniquePathInDir(dest_dir_path, &dest_file_path, &dest_path_cost);
 
@@ -599,10 +599,10 @@ TEST_F(LocalFileSystemOperationTest, TestCopyFailureByQuota) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcFileAndOverwrite) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(CreateUniqueFileInDir(dest_dir_path));
 
   operation()->Copy(URLForPath(src_file_path), URLForPath(dest_file_path),
                     RecordStatusCallback());
@@ -616,10 +616,10 @@ TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcFileAndOverwrite) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcFileAndNew) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(dest_dir_path.Append(FILE_PATH_LITERAL("NewFile")));
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_file_path(CreateUniqueFileInDir(src_dir_path));
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(dest_dir_path.Append(FILE_PATH_LITERAL("NewFile")));
 
   operation()->Copy(URLForPath(src_file_path), URLForPath(dest_file_path),
                     RecordStatusCallback());
@@ -633,8 +633,8 @@ TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcFileAndNew) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcDirAndOverwrite) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
   operation()->Copy(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
@@ -653,9 +653,9 @@ TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcDirAndOverwrite) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcDirAndNew) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath dest_parent_dir_path(CreateUniqueDir());
-  FilePath dest_child_dir_path(dest_parent_dir_path.
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath dest_parent_dir_path(CreateUniqueDir());
+  base::FilePath dest_child_dir_path(dest_parent_dir_path.
       Append(FILE_PATH_LITERAL("NewDirectory")));
 
   operation()->Copy(URLForPath(src_dir_path), URLForPath(dest_child_dir_path),
@@ -670,12 +670,12 @@ TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcDirAndNew) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcDirRecursive) {
-  FilePath src_dir_path(CreateUniqueDir());
-  FilePath child_dir_path(CreateUniqueDirInDir(src_dir_path));
-  FilePath grandchild_file_path(
+  base::FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath child_dir_path(CreateUniqueDirInDir(src_dir_path));
+  base::FilePath grandchild_file_path(
       CreateUniqueFileInDir(child_dir_path));
 
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
   operation()->Copy(URLForPath(src_dir_path), URLForPath(dest_dir_path),
                     RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -696,13 +696,13 @@ TEST_F(LocalFileSystemOperationTest, TestCopySuccessSrcDirRecursive) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopyInForeignFileSuccess) {
-  FilePath src_local_disk_file_path;
+  base::FilePath src_local_disk_file_path;
   file_util::CreateTemporaryFile(&src_local_disk_file_path);
   const char test_data[] = "foo";
   int data_size = ARRAYSIZE_UNSAFE(test_data);
   file_util::WriteFile(src_local_disk_file_path, test_data, data_size);
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(dest_dir_path.Append(
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(dest_dir_path.Append(
       src_local_disk_file_path.BaseName()));
   FileSystemURL dest_file_url = URLForPath(dest_file_path);
   int64 before_usage;
@@ -729,14 +729,14 @@ TEST_F(LocalFileSystemOperationTest, TestCopyInForeignFileSuccess) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCopyInForeignFileFailureByQuota) {
-  FilePath src_local_disk_file_path;
+  base::FilePath src_local_disk_file_path;
   file_util::CreateTemporaryFile(&src_local_disk_file_path);
   const char test_data[] = "foo";
   file_util::WriteFile(src_local_disk_file_path, test_data,
                        ARRAYSIZE_UNSAFE(test_data));
 
-  FilePath dest_dir_path(CreateUniqueDir());
-  FilePath dest_file_path(dest_dir_path.Append(
+  base::FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_file_path(dest_dir_path.Append(
       src_local_disk_file_path.BaseName()));
   FileSystemURL dest_file_url = URLForPath(dest_file_path);
 
@@ -756,8 +756,8 @@ TEST_F(LocalFileSystemOperationTest, TestCopyInForeignFileFailureByQuota) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateFileFailure) {
   // Already existing file and exclusive true.
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   operation()->CreateFile(URLForPath(file_path), true,
                           RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -767,8 +767,8 @@ TEST_F(LocalFileSystemOperationTest, TestCreateFileFailure) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateFileSuccessFileExists) {
   // Already existing file and exclusive false.
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   operation()->CreateFile(URLForPath(file_path), false,
                           RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -781,8 +781,8 @@ TEST_F(LocalFileSystemOperationTest, TestCreateFileSuccessFileExists) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateFileSuccessExclusive) {
   // File doesn't exist but exclusive is true.
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(dir_path.Append(FILE_PATH_LITERAL("FileDoesntExist")));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(dir_path.Append(FILE_PATH_LITERAL("FileDoesntExist")));
   operation()->CreateFile(URLForPath(file_path), true,
                           RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -793,8 +793,8 @@ TEST_F(LocalFileSystemOperationTest, TestCreateFileSuccessExclusive) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateFileSuccessFileDoesntExist) {
   // Non existing file.
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(dir_path.Append(FILE_PATH_LITERAL("FileDoesntExist")));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(dir_path.Append(FILE_PATH_LITERAL("FileDoesntExist")));
   operation()->CreateFile(URLForPath(file_path), false,
                           RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -805,9 +805,9 @@ TEST_F(LocalFileSystemOperationTest, TestCreateFileSuccessFileDoesntExist) {
 TEST_F(LocalFileSystemOperationTest,
        TestCreateDirFailureDestParentDoesntExist) {
   // Dest. parent path does not exist.
-  FilePath nonexisting_path(FilePath(
+  base::FilePath nonexisting_path(base::FilePath(
       FILE_PATH_LITERAL("DirDoesntExist")));
-  FilePath nonexisting_file_path(nonexisting_path.Append(
+  base::FilePath nonexisting_file_path(nonexisting_path.Append(
       FILE_PATH_LITERAL("FileDoesntExist")));
   operation()->CreateDirectory(URLForPath(nonexisting_file_path), false, false,
                                RecordStatusCallback());
@@ -818,7 +818,7 @@ TEST_F(LocalFileSystemOperationTest,
 
 TEST_F(LocalFileSystemOperationTest, TestCreateDirFailureDirExists) {
   // Exclusive and dir existing at path.
-  FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
   operation()->CreateDirectory(URLForPath(src_dir_path), true, false,
                                RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -828,8 +828,8 @@ TEST_F(LocalFileSystemOperationTest, TestCreateDirFailureDirExists) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateDirFailureFileExists) {
   // Exclusive true and file existing at path.
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   operation()->CreateDirectory(URLForPath(file_path), true, false,
                                RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -839,7 +839,7 @@ TEST_F(LocalFileSystemOperationTest, TestCreateDirFailureFileExists) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateDirSuccess) {
   // Dir exists and exclusive is false.
-  FilePath dir_path(CreateUniqueDir());
+  base::FilePath dir_path(CreateUniqueDir());
   operation()->CreateDirectory(URLForPath(dir_path), false, false,
                                RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -847,7 +847,7 @@ TEST_F(LocalFileSystemOperationTest, TestCreateDirSuccess) {
   EXPECT_TRUE(change_observer()->HasNoChange());
 
   // Dir doesn't exist.
-  FilePath nonexisting_dir_path(FilePath(
+  base::FilePath nonexisting_dir_path(base::FilePath(
       FILE_PATH_LITERAL("nonexistingdir")));
   operation()->CreateDirectory(URLForPath(nonexisting_dir_path), false, false,
                                RecordStatusCallback());
@@ -859,7 +859,7 @@ TEST_F(LocalFileSystemOperationTest, TestCreateDirSuccess) {
 
 TEST_F(LocalFileSystemOperationTest, TestCreateDirSuccessExclusive) {
   // Dir doesn't exist.
-  FilePath nonexisting_dir_path(FilePath(
+  base::FilePath nonexisting_dir_path(base::FilePath(
       FILE_PATH_LITERAL("nonexistingdir")));
 
   operation()->CreateDirectory(URLForPath(nonexisting_dir_path), true, false,
@@ -872,7 +872,7 @@ TEST_F(LocalFileSystemOperationTest, TestCreateDirSuccessExclusive) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestExistsAndMetadataFailure) {
-  FilePath nonexisting_dir_path(FilePath(
+  base::FilePath nonexisting_dir_path(base::FilePath(
       FILE_PATH_LITERAL("nonexistingdir")));
   operation()->GetMetadata(URLForPath(nonexisting_dir_path),
                            RecordMetadataCallback());
@@ -893,7 +893,7 @@ TEST_F(LocalFileSystemOperationTest, TestExistsAndMetadataFailure) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestExistsAndMetadataSuccess) {
-  FilePath dir_path(CreateUniqueDir());
+  base::FilePath dir_path(CreateUniqueDir());
   int read_access = 0;
 
   operation()->DirectoryExists(URLForPath(dir_path),
@@ -906,10 +906,10 @@ TEST_F(LocalFileSystemOperationTest, TestExistsAndMetadataSuccess) {
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(base::PLATFORM_FILE_OK, status());
   EXPECT_TRUE(info().is_directory);
-  EXPECT_EQ(FilePath(), path());
+  EXPECT_EQ(base::FilePath(), path());
   ++read_access;
 
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   operation()->FileExists(URLForPath(file_path), RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(base::PLATFORM_FILE_OK, status());
@@ -928,12 +928,12 @@ TEST_F(LocalFileSystemOperationTest, TestExistsAndMetadataSuccess) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestTypeMismatchErrors) {
-  FilePath dir_path(CreateUniqueDir());
+  base::FilePath dir_path(CreateUniqueDir());
   operation()->FileExists(URLForPath(dir_path), RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(base::PLATFORM_FILE_ERROR_NOT_A_FILE, status());
 
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   ASSERT_FALSE(file_path.empty());
   operation()->DirectoryExists(URLForPath(file_path), RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -942,7 +942,7 @@ TEST_F(LocalFileSystemOperationTest, TestTypeMismatchErrors) {
 
 TEST_F(LocalFileSystemOperationTest, TestReadDirFailure) {
   // Path doesn't exist
-  FilePath nonexisting_dir_path(FilePath(
+  base::FilePath nonexisting_dir_path(base::FilePath(
       FILE_PATH_LITERAL("NonExistingDir")));
   file_util::EnsureEndsWithSeparator(&nonexisting_dir_path);
   operation()->ReadDirectory(URLForPath(nonexisting_dir_path),
@@ -951,8 +951,8 @@ TEST_F(LocalFileSystemOperationTest, TestReadDirFailure) {
   EXPECT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, status());
 
   // File exists.
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   operation()->ReadDirectory(URLForPath(file_path),
                              RecordReadDirectoryCallback());
   MessageLoop::current()->RunUntilIdle();
@@ -965,9 +965,9 @@ TEST_F(LocalFileSystemOperationTest, TestReadDirSuccess) {
   //       |       |
   //  child_dir  child_file
   // Verify reading parent_dir.
-  FilePath parent_dir_path(CreateUniqueDir());
-  FilePath child_file_path(CreateUniqueFileInDir(parent_dir_path));
-  FilePath child_dir_path(CreateUniqueDirInDir(parent_dir_path));
+  base::FilePath parent_dir_path(CreateUniqueDir());
+  base::FilePath child_file_path(CreateUniqueFileInDir(parent_dir_path));
+  base::FilePath child_dir_path(CreateUniqueDirInDir(parent_dir_path));
   ASSERT_FALSE(child_dir_path.empty());
 
   operation()->ReadDirectory(URLForPath(parent_dir_path),
@@ -991,7 +991,7 @@ TEST_F(LocalFileSystemOperationTest, TestReadDirSuccess) {
 
 TEST_F(LocalFileSystemOperationTest, TestRemoveFailure) {
   // Path doesn't exist.
-  FilePath nonexisting_path(FilePath(
+  base::FilePath nonexisting_path(base::FilePath(
       FILE_PATH_LITERAL("NonExistingDir")));
   file_util::EnsureEndsWithSeparator(&nonexisting_path);
 
@@ -1006,9 +1006,9 @@ TEST_F(LocalFileSystemOperationTest, TestRemoveFailure) {
   //       |       |
   //  child_dir  child_file
   // Verify deleting parent_dir.
-  FilePath parent_dir_path(CreateUniqueDir());
-  FilePath child_file_path(CreateUniqueFileInDir(parent_dir_path));
-  FilePath child_dir_path(CreateUniqueDirInDir(parent_dir_path));
+  base::FilePath parent_dir_path(CreateUniqueDir());
+  base::FilePath child_file_path(CreateUniqueFileInDir(parent_dir_path));
+  base::FilePath child_dir_path(CreateUniqueDirInDir(parent_dir_path));
   ASSERT_FALSE(child_dir_path.empty());
 
   operation()->Remove(URLForPath(parent_dir_path), false /* recursive */,
@@ -1020,7 +1020,7 @@ TEST_F(LocalFileSystemOperationTest, TestRemoveFailure) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestRemoveSuccess) {
-  FilePath empty_dir_path(CreateUniqueDir());
+  base::FilePath empty_dir_path(CreateUniqueDir());
   EXPECT_TRUE(DirectoryExists(empty_dir_path));
 
   operation()->Remove(URLForPath(empty_dir_path), false /* recursive */,
@@ -1037,9 +1037,9 @@ TEST_F(LocalFileSystemOperationTest, TestRemoveSuccess) {
   //       |       |
   //  child_dir  child_file
   // Verify deleting parent_dir.
-  FilePath parent_dir_path(CreateUniqueDir());
-  FilePath child_file_path(CreateUniqueFileInDir(parent_dir_path));
-  FilePath child_dir_path(CreateUniqueDirInDir(parent_dir_path));
+  base::FilePath parent_dir_path(CreateUniqueDir());
+  base::FilePath child_file_path(CreateUniqueFileInDir(parent_dir_path));
+  base::FilePath child_dir_path(CreateUniqueDirInDir(parent_dir_path));
   ASSERT_FALSE(child_dir_path.empty());
 
   operation()->Remove(URLForPath(parent_dir_path), true /* recursive */,
@@ -1054,8 +1054,8 @@ TEST_F(LocalFileSystemOperationTest, TestRemoveSuccess) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestTruncate) {
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
 
   char test_data[] = "test data";
   int data_size = static_cast<int>(sizeof(test_data));
@@ -1118,8 +1118,8 @@ TEST_F(LocalFileSystemOperationTest, TestTruncate) {
 TEST_F(LocalFileSystemOperationTest, TestTruncateFailureByQuota) {
   base::PlatformFileInfo info;
 
-  FilePath dir_path(CreateUniqueDir());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath dir_path(CreateUniqueDir());
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
 
   GrantQuotaForCurrentUsage();
   AddQuota(10);
@@ -1143,8 +1143,8 @@ TEST_F(LocalFileSystemOperationTest, TestTruncateFailureByQuota) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestTouchFile) {
-  FilePath file_path(CreateUniqueFileInDir(FilePath()));
-  FilePath platform_path = PlatformPath(file_path);
+  base::FilePath file_path(CreateUniqueFileInDir(base::FilePath()));
+  base::FilePath platform_path = PlatformPath(file_path);
 
   base::PlatformFileInfo info;
 
@@ -1176,12 +1176,12 @@ TEST_F(LocalFileSystemOperationTest, TestTouchFile) {
 }
 
 TEST_F(LocalFileSystemOperationTest, TestCreateSnapshotFile) {
-  FilePath dir_path(CreateUniqueDir());
+  base::FilePath dir_path(CreateUniqueDir());
 
   // Create a file for the testing.
   operation()->DirectoryExists(URLForPath(dir_path),
                                RecordStatusCallback());
-  FilePath file_path(CreateUniqueFileInDir(dir_path));
+  base::FilePath file_path(CreateUniqueFileInDir(dir_path));
   operation()->FileExists(URLForPath(file_path), RecordStatusCallback());
   MessageLoop::current()->RunUntilIdle();
   EXPECT_EQ(base::PLATFORM_FILE_OK, status());
diff --git a/webkit/fileapi/local_file_system_operation_write_unittest.cc b/webkit/fileapi/local_file_system_operation_write_unittest.cc
index 4a8cd479559c8c..5841222c927ab5 100644
--- a/webkit/fileapi/local_file_system_operation_write_unittest.cc
+++ b/webkit/fileapi/local_file_system_operation_write_unittest.cc
@@ -43,7 +43,7 @@ void AssertStatusEq(base::PlatformFileError expected,
 
 class MockQuotaManager : public QuotaManager {
  public:
-  MockQuotaManager(const FilePath& base_dir, int64 quota)
+  MockQuotaManager(const base::FilePath& base_dir, int64 quota)
       : QuotaManager(false /* is_incognito */, base_dir,
                      base::MessageLoopProxy::current(),
                      base::MessageLoopProxy::current(),
@@ -109,7 +109,7 @@ class LocalFileSystemOperationWriteTest
     return &change_observer_;
   }
 
-  FileSystemURL URLForPath(const FilePath& path) const {
+  FileSystemURL URLForPath(const base::FilePath& path) const {
     return test_helper_.CreateURL(path);
   }
 
@@ -153,7 +153,7 @@ class LocalFileSystemOperationWriteTest
   MessageLoop loop_;
 
   base::ScopedTempDir dir_;
-  FilePath virtual_path_;
+  base::FilePath virtual_path_;
 
   // For post-operation status.
   base::PlatformFileError status_;
@@ -172,13 +172,13 @@ class LocalFileSystemOperationWriteTest
 
 void LocalFileSystemOperationWriteTest::SetUp() {
   ASSERT_TRUE(dir_.CreateUniqueTempDir());
-  FilePath base_dir = dir_.path().AppendASCII("filesystem");
+  base::FilePath base_dir = dir_.path().AppendASCII("filesystem");
 
   quota_manager_ = new MockQuotaManager(base_dir, 1024);
   test_helper_.SetUp(base_dir,
                      false /* unlimited quota */,
                      quota_manager_->proxy());
-  virtual_path_ = FilePath(FILE_PATH_LITERAL("temporary file"));
+  virtual_path_ = base::FilePath(FILE_PATH_LITERAL("temporary file"));
 
   operation()->CreateFile(
       URLForPath(virtual_path_), true /* exclusive */,
@@ -248,7 +248,7 @@ TEST_F(LocalFileSystemOperationWriteTest, TestWriteInvalidFile) {
   ScopedTextBlob blob(url_request_context_, blob_url, "It\'ll not be written.");
 
   operation()->Write(&url_request_context_,
-                     URLForPath(FilePath(FILE_PATH_LITERAL("nonexist"))),
+                     URLForPath(base::FilePath(FILE_PATH_LITERAL("nonexist"))),
                      blob_url, 0, RecordWriteCallback());
   MessageLoop::current()->Run();
 
@@ -260,7 +260,7 @@ TEST_F(LocalFileSystemOperationWriteTest, TestWriteInvalidFile) {
 }
 
 TEST_F(LocalFileSystemOperationWriteTest, TestWriteDir) {
-  FilePath virtual_dir_path(FILE_PATH_LITERAL("d"));
+  base::FilePath virtual_dir_path(FILE_PATH_LITERAL("d"));
   operation()->CreateDirectory(
       URLForPath(virtual_dir_path),
       true /* exclusive */, false /* recursive */,
@@ -330,7 +330,7 @@ TEST_F(LocalFileSystemOperationWriteTest, TestImmediateCancelFailingWrite) {
 
   FileSystemOperation* write_operation = operation();
   write_operation->Write(&url_request_context_,
-                         URLForPath(FilePath(FILE_PATH_LITERAL("nonexist"))),
+                         URLForPath(base::FilePath(FILE_PATH_LITERAL("nonexist"))),
                          blob_url, 0, RecordWriteCallback());
   write_operation->Cancel(RecordCancelCallback());
   // We use RunAllPendings() instead of Run() here, because we won't dispatch
diff --git a/webkit/fileapi/local_file_system_quota_unittest.cc b/webkit/fileapi/local_file_system_quota_unittest.cc
index 1e7f6a732eb9b6..0e391024edea9e 100644
--- a/webkit/fileapi/local_file_system_quota_unittest.cc
+++ b/webkit/fileapi/local_file_system_quota_unittest.cc
@@ -72,13 +72,13 @@ class LocalFileSystemQuotaTest
     return context;
   }
 
-  void PrepareFileSet(const FilePath& virtual_path);
+  void PrepareFileSet(const base::FilePath& virtual_path);
 
-  FileSystemURL URLForPath(const FilePath& path) const {
+  FileSystemURL URLForPath(const base::FilePath& path) const {
     return test_helper_.CreateURL(path);
   }
 
-  FilePath PlatformPath(const FilePath& virtual_path) {
+  base::FilePath PlatformPath(const base::FilePath& virtual_path) {
     return test_helper_.GetLocalPath(virtual_path);
   }
 
@@ -100,24 +100,24 @@ class LocalFileSystemQuotaTest
     MessageLoop::current()->RunUntilIdle();
   }
 
-  bool FileExists(const FilePath& virtual_path) {
+  bool FileExists(const base::FilePath& virtual_path) {
     FileSystemURL url = test_helper_.CreateURL(virtual_path);
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     scoped_ptr<FileSystemOperationContext> context(NewContext());
     base::PlatformFileError error = file_util()->GetFileInfo(
         context.get(), url, &file_info, &platform_path);
     return error == base::PLATFORM_FILE_OK;
   }
 
-  bool DirectoryExists(const FilePath& virtual_path) {
+  bool DirectoryExists(const base::FilePath& virtual_path) {
     FileSystemURL path = test_helper_.CreateURL(virtual_path);
     scoped_ptr<FileSystemOperationContext> context(NewContext());
     return FileUtilHelper::DirectoryExists(context.get(), file_util(), path);
   }
 
-  FilePath CreateUniqueFileInDir(const FilePath& virtual_dir_path) {
-    FilePath file_name = FilePath::FromUTF8Unsafe(
+  base::FilePath CreateUniqueFileInDir(const base::FilePath& virtual_dir_path) {
+    base::FilePath file_name = base::FilePath::FromUTF8Unsafe(
         "tmpfile-" + base::IntToString(next_unique_path_suffix_++));
     FileSystemURL url = test_helper_.CreateURL(
         virtual_dir_path.Append(file_name));
@@ -130,8 +130,8 @@ class LocalFileSystemQuotaTest
     return url.path();
   }
 
-  FilePath CreateUniqueDirInDir(const FilePath& virtual_dir_path) {
-    FilePath dir_name = FilePath::FromUTF8Unsafe(
+  base::FilePath CreateUniqueDirInDir(const base::FilePath& virtual_dir_path) {
+    base::FilePath dir_name = base::FilePath::FromUTF8Unsafe(
         "tmpdir-" + base::IntToString(next_unique_path_suffix_++));
     FileSystemURL url = test_helper_.CreateURL(
         virtual_dir_path.Append(dir_name));
@@ -142,15 +142,15 @@ class LocalFileSystemQuotaTest
     return url.path();
   }
 
-  FilePath CreateUniqueDir() {
-    return CreateUniqueDirInDir(FilePath());
+  base::FilePath CreateUniqueDir() {
+    return CreateUniqueDirInDir(base::FilePath());
   }
 
-  FilePath child_dir_path_;
-  FilePath child_file1_path_;
-  FilePath child_file2_path_;
-  FilePath grandchild_file1_path_;
-  FilePath grandchild_file2_path_;
+  base::FilePath child_dir_path_;
+  base::FilePath child_file1_path_;
+  base::FilePath child_file2_path_;
+  base::FilePath grandchild_file1_path_;
+  base::FilePath grandchild_file2_path_;
 
   int64 child_path_cost_;
   int64 grandchild_path_cost_;
@@ -186,7 +186,7 @@ class LocalFileSystemQuotaTest
 
 void LocalFileSystemQuotaTest::SetUp() {
   ASSERT_TRUE(work_dir_.CreateUniqueTempDir());
-  FilePath filesystem_dir_path = work_dir_.path().AppendASCII("filesystem");
+  base::FilePath filesystem_dir_path = work_dir_.path().AppendASCII("filesystem");
   ASSERT_TRUE(file_util::CreateDirectory(filesystem_dir_path));
 
   quota_manager_ = new quota::QuotaManager(
@@ -217,7 +217,7 @@ void LocalFileSystemQuotaTest::OnGetUsageAndQuota(
   quota_ = quota;
 }
 
-void LocalFileSystemQuotaTest::PrepareFileSet(const FilePath& virtual_path) {
+void LocalFileSystemQuotaTest::PrepareFileSet(const base::FilePath& virtual_path) {
   int64 usage = SizeByQuotaUtil();
   child_dir_path_ = CreateUniqueDirInDir(virtual_path);
   child_file1_path_ = CreateUniqueFileInDir(virtual_path);
@@ -231,10 +231,10 @@ void LocalFileSystemQuotaTest::PrepareFileSet(const FilePath& virtual_path) {
 }
 
 TEST_F(LocalFileSystemQuotaTest, TestMoveSuccessSrcDirRecursive) {
-  FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
   int src_path_cost = SizeByQuotaUtil();
   PrepareFileSet(src_dir_path);
-  FilePath dest_dir_path(CreateUniqueDir());
+  base::FilePath dest_dir_path(CreateUniqueDir());
 
   EXPECT_EQ(0, ActualFileSize());
   int total_path_cost = SizeByQuotaUtil();
@@ -279,10 +279,10 @@ TEST_F(LocalFileSystemQuotaTest, TestMoveSuccessSrcDirRecursive) {
 }
 
 TEST_F(LocalFileSystemQuotaTest, TestCopySuccessSrcDirRecursive) {
-  FilePath src_dir_path(CreateUniqueDir());
+  base::FilePath src_dir_path(CreateUniqueDir());
   PrepareFileSet(src_dir_path);
-  FilePath dest_dir1_path(CreateUniqueDir());
-  FilePath dest_dir2_path(CreateUniqueDir());
+  base::FilePath dest_dir1_path(CreateUniqueDir());
+  base::FilePath dest_dir2_path(CreateUniqueDir());
 
   EXPECT_EQ(0, ActualFileSize());
   int total_path_cost = SizeByQuotaUtil();
diff --git a/webkit/fileapi/local_file_system_test_helper.cc b/webkit/fileapi/local_file_system_test_helper.cc
index e3dbe612c4fe98..fe206f1641fe6f 100644
--- a/webkit/fileapi/local_file_system_test_helper.cc
+++ b/webkit/fileapi/local_file_system_test_helper.cc
@@ -38,7 +38,7 @@ LocalFileSystemTestOriginHelper::LocalFileSystemTestOriginHelper()
 LocalFileSystemTestOriginHelper::~LocalFileSystemTestOriginHelper() {
 }
 
-void LocalFileSystemTestOriginHelper::SetUp(const FilePath& base_dir) {
+void LocalFileSystemTestOriginHelper::SetUp(const base::FilePath& base_dir) {
   SetUp(base_dir, false, NULL);
 }
 
@@ -50,17 +50,17 @@ void LocalFileSystemTestOriginHelper::SetUp(
 
   // Prepare the origin's root directory.
   file_system_context_->GetMountPointProvider(type_)->
-      GetFileSystemRootPathOnFileThread(CreateURL(FilePath()),
+      GetFileSystemRootPathOnFileThread(CreateURL(base::FilePath()),
                                         true /* create */);
 
   // Initialize the usage cache file.
-  FilePath usage_cache_path = GetUsageCachePath();
+  base::FilePath usage_cache_path = GetUsageCachePath();
   if (!usage_cache_path.empty())
     FileSystemUsageCache::UpdateUsage(usage_cache_path, 0);
 }
 
 void LocalFileSystemTestOriginHelper::SetUp(
-    const FilePath& base_dir,
+    const base::FilePath& base_dir,
     bool unlimited_quota,
     quota::QuotaManagerProxy* quota_manager_proxy) {
   scoped_refptr<quota::MockSpecialStoragePolicy> special_storage_policy =
@@ -79,11 +79,11 @@ void LocalFileSystemTestOriginHelper::SetUp(
   // Prepare the origin's root directory.
   FileSystemMountPointProvider* mount_point_provider =
       file_system_context_->GetMountPointProvider(type_);
-  mount_point_provider->GetFileSystemRootPathOnFileThread(CreateURL(FilePath()),
+  mount_point_provider->GetFileSystemRootPathOnFileThread(CreateURL(base::FilePath()),
                                                           true /* create */);
 
   // Initialize the usage cache file.
-  FilePath usage_cache_path = GetUsageCachePath();
+  base::FilePath usage_cache_path = GetUsageCachePath();
   if (!usage_cache_path.empty())
     FileSystemUsageCache::UpdateUsage(usage_cache_path, 0);
 }
@@ -93,33 +93,33 @@ void LocalFileSystemTestOriginHelper::TearDown() {
   MessageLoop::current()->RunUntilIdle();
 }
 
-FilePath LocalFileSystemTestOriginHelper::GetOriginRootPath() const {
+base::FilePath LocalFileSystemTestOriginHelper::GetOriginRootPath() const {
   return file_system_context_->GetMountPointProvider(type_)->
-      GetFileSystemRootPathOnFileThread(CreateURL(FilePath()), false);
+      GetFileSystemRootPathOnFileThread(CreateURL(base::FilePath()), false);
 }
 
-FilePath LocalFileSystemTestOriginHelper::GetLocalPath(const FilePath& path) {
+base::FilePath LocalFileSystemTestOriginHelper::GetLocalPath(const base::FilePath& path) {
   DCHECK(file_util_);
-  FilePath local_path;
+  base::FilePath local_path;
   scoped_ptr<FileSystemOperationContext> context(NewOperationContext());
   file_util_->GetLocalFilePath(context.get(), CreateURL(path), &local_path);
   return local_path;
 }
 
-FilePath LocalFileSystemTestOriginHelper::GetLocalPathFromASCII(
+base::FilePath LocalFileSystemTestOriginHelper::GetLocalPathFromASCII(
     const std::string& path) {
-  return GetLocalPath(FilePath().AppendASCII(path));
+  return GetLocalPath(base::FilePath().AppendASCII(path));
 }
 
-FilePath LocalFileSystemTestOriginHelper::GetUsageCachePath() const {
+base::FilePath LocalFileSystemTestOriginHelper::GetUsageCachePath() const {
   if (type_ != kFileSystemTypeTemporary &&
       type_ != kFileSystemTypePersistent)
-    return FilePath();
+    return base::FilePath();
   return file_system_context_->
       sandbox_provider()->GetUsageCachePathForOriginAndType(origin_, type_);
 }
 
-FileSystemURL LocalFileSystemTestOriginHelper::CreateURL(const FilePath& path)
+FileSystemURL LocalFileSystemTestOriginHelper::CreateURL(const base::FilePath& path)
     const {
   return file_system_context_->CreateCrackedFileSystemURL(origin_, type_, path);
 }
@@ -163,7 +163,7 @@ LocalFileSystemOperation* LocalFileSystemTestOriginHelper::NewOperation() {
       NewOperationContext());
   LocalFileSystemOperation* operation = static_cast<LocalFileSystemOperation*>(
       file_system_context_->CreateFileSystemOperation(
-          CreateURL(FilePath()), NULL));
+          CreateURL(base::FilePath()), NULL));
   return operation;
 }
 
diff --git a/webkit/fileapi/local_file_system_test_helper.h b/webkit/fileapi/local_file_system_test_helper.h
index c6cf8c746c99ba..6dbebc68882e7c 100644
--- a/webkit/fileapi/local_file_system_test_helper.h
+++ b/webkit/fileapi/local_file_system_test_helper.h
@@ -15,12 +15,14 @@
 #include "webkit/fileapi/file_system_util.h"
 #include "webkit/quota/quota_types.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace quota {
 class QuotaManagerProxy;
 }
 
-class FilePath;
-
 namespace fileapi {
 
 class FileSystemContext;
@@ -37,27 +39,27 @@ class LocalFileSystemTestOriginHelper {
   LocalFileSystemTestOriginHelper();
   ~LocalFileSystemTestOriginHelper();
 
-  void SetUp(const FilePath& base_dir);
+  void SetUp(const base::FilePath& base_dir);
   // If you want to use more than one LocalFileSystemTestOriginHelper in
   // a single base directory, they have to share a context, so that they don't
   // have multiple databases fighting over the lock to the origin directory
   // [deep down inside ObfuscatedFileUtil].
   void SetUp(FileSystemContext* file_system_context);
-  void SetUp(const FilePath& base_dir,
+  void SetUp(const base::FilePath& base_dir,
              bool unlimited_quota,
              quota::QuotaManagerProxy* quota_manager_proxy);
   void TearDown();
 
-  FilePath GetOriginRootPath() const;
-  FilePath GetLocalPath(const FilePath& path);
-  FilePath GetLocalPathFromASCII(const std::string& path);
+  base::FilePath GetOriginRootPath() const;
+  base::FilePath GetLocalPath(const base::FilePath& path);
+  base::FilePath GetLocalPathFromASCII(const std::string& path);
 
   // Returns empty path if filesystem type is neither temporary nor persistent.
-  FilePath GetUsageCachePath() const;
+  base::FilePath GetUsageCachePath() const;
 
-  FileSystemURL CreateURL(const FilePath& path) const;
+  FileSystemURL CreateURL(const base::FilePath& path) const;
   FileSystemURL CreateURLFromUTF8(const std::string& utf8) const {
-    return CreateURL(FilePath::FromUTF8Unsafe(utf8));
+    return CreateURL(base::FilePath::FromUTF8Unsafe(utf8));
   }
 
   // Helper methods for same-FileUtil copy/move.
diff --git a/webkit/fileapi/local_file_util.cc b/webkit/fileapi/local_file_util.cc
index 0cecdcab71802c..4b533c9b8bff17 100644
--- a/webkit/fileapi/local_file_util.cc
+++ b/webkit/fileapi/local_file_util.cc
@@ -20,8 +20,8 @@ using base::PlatformFileError;
 
 class LocalFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
  public:
-  LocalFileEnumerator(const FilePath& platform_root_path,
-                      const FilePath& virtual_root_path,
+  LocalFileEnumerator(const base::FilePath& platform_root_path,
+                      const base::FilePath& virtual_root_path,
                       bool recursive,
                       int file_type)
       : file_enum_(platform_root_path, recursive, file_type),
@@ -34,7 +34,7 @@ class LocalFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
 
   ~LocalFileEnumerator() {}
 
-  virtual FilePath Next() OVERRIDE;
+  virtual base::FilePath Next() OVERRIDE;
   virtual int64 Size() OVERRIDE;
   virtual base::Time LastModifiedTime() OVERRIDE;
   virtual bool IsDirectory() OVERRIDE;
@@ -42,12 +42,12 @@ class LocalFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
  private:
   file_util::FileEnumerator file_enum_;
   file_util::FileEnumerator::FindInfo file_util_info_;
-  FilePath platform_root_path_;
-  FilePath virtual_root_path_;
+  base::FilePath platform_root_path_;
+  base::FilePath virtual_root_path_;
 };
 
-FilePath LocalFileEnumerator::Next() {
-  FilePath next = file_enum_.Next();
+base::FilePath LocalFileEnumerator::Next() {
+  base::FilePath next = file_enum_.Next();
   // Don't return symlinks.
   while (!next.empty() && file_util::IsLink(next))
     next = file_enum_.Next();
@@ -55,7 +55,7 @@ FilePath LocalFileEnumerator::Next() {
     return next;
   file_enum_.GetFindInfo(&file_util_info_);
 
-  FilePath path;
+  base::FilePath path;
   platform_root_path_.AppendRelativePath(next, &path);
   return virtual_root_path_.Append(path);
 }
@@ -82,7 +82,7 @@ PlatformFileError LocalFileUtil::CreateOrOpen(
     FileSystemOperationContext* context,
     const FileSystemURL& url, int file_flags,
     base::PlatformFile* file_handle, bool* created) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -99,7 +99,7 @@ PlatformFileError LocalFileUtil::EnsureFileExists(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     bool* created) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -111,7 +111,7 @@ PlatformFileError LocalFileUtil::CreateDirectory(
     const FileSystemURL& url,
     bool exclusive,
     bool recursive) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -122,8 +122,8 @@ PlatformFileError LocalFileUtil::GetFileInfo(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     base::PlatformFileInfo* file_info,
-    FilePath* platform_file_path) {
-  FilePath file_path;
+    base::FilePath* platform_file_path) {
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -141,7 +141,7 @@ scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> LocalFileUtil::
         FileSystemOperationContext* context,
         const FileSystemURL& root_url,
         bool recursive) {
-  FilePath file_path;
+  base::FilePath file_path;
   if (GetLocalFilePath(context, root_url, &file_path) !=
       base::PLATFORM_FILE_OK) {
     return make_scoped_ptr(new EmptyFileEnumerator)
@@ -157,11 +157,11 @@ scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> LocalFileUtil::
 PlatformFileError LocalFileUtil::GetLocalFilePath(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
-    FilePath* local_file_path) {
+    base::FilePath* local_file_path) {
   FileSystemMountPointProvider* provider =
       context->file_system_context()->GetMountPointProvider(url.type());
   DCHECK(provider);
-  FilePath root = provider->GetFileSystemRootPathOnFileThread(url, false);
+  base::FilePath root = provider->GetFileSystemRootPathOnFileThread(url, false);
   if (root.empty())
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
   *local_file_path = root.Append(url.path());
@@ -173,7 +173,7 @@ PlatformFileError LocalFileUtil::Touch(
     const FileSystemURL& url,
     const base::Time& last_access_time,
     const base::Time& last_modified_time) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -184,7 +184,7 @@ PlatformFileError LocalFileUtil::Truncate(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     int64 length) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -196,12 +196,12 @@ PlatformFileError LocalFileUtil::CopyOrMoveFile(
     const FileSystemURL& src_url,
     const FileSystemURL& dest_url,
     bool copy) {
-  FilePath src_file_path;
+  base::FilePath src_file_path;
   PlatformFileError error = GetLocalFilePath(context, src_url, &src_file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
 
-  FilePath dest_file_path;
+  base::FilePath dest_file_path;
   error = GetLocalFilePath(context, dest_url, &dest_file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -211,12 +211,12 @@ PlatformFileError LocalFileUtil::CopyOrMoveFile(
 
 PlatformFileError LocalFileUtil::CopyInForeignFile(
     FileSystemOperationContext* context,
-    const FilePath& src_file_path,
+    const base::FilePath& src_file_path,
     const FileSystemURL& dest_url) {
   if (src_file_path.empty())
     return base::PLATFORM_FILE_ERROR_INVALID_OPERATION;
 
-  FilePath dest_file_path;
+  base::FilePath dest_file_path;
   PlatformFileError error =
       GetLocalFilePath(context, dest_url, &dest_file_path);
   if (error != base::PLATFORM_FILE_OK)
@@ -227,7 +227,7 @@ PlatformFileError LocalFileUtil::CopyInForeignFile(
 PlatformFileError LocalFileUtil::DeleteFile(
     FileSystemOperationContext* context,
     const FileSystemURL& url) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -237,7 +237,7 @@ PlatformFileError LocalFileUtil::DeleteFile(
 PlatformFileError LocalFileUtil::DeleteDirectory(
     FileSystemOperationContext* context,
     const FileSystemURL& url) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -248,7 +248,7 @@ base::PlatformFileError LocalFileUtil::CreateSnapshotFile(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     base::PlatformFileInfo* file_info,
-    FilePath* platform_path,
+    base::FilePath* platform_path,
     SnapshotFilePolicy* policy) {
   DCHECK(policy);
   DCHECK(file_info);
diff --git a/webkit/fileapi/local_file_util.h b/webkit/fileapi/local_file_util.h
index bbe51f18c5b53d..7f19a687f69be6 100644
--- a/webkit/fileapi/local_file_util.h
+++ b/webkit/fileapi/local_file_util.h
@@ -12,10 +12,10 @@
 #include "webkit/storage/webkit_storage_export.h"
 
 namespace base {
+class FilePath;
 class Time;
 }
 
-class FilePath;
 class GURL;
 
 namespace fileapi {
@@ -50,7 +50,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE LocalFileUtil : public FileSystemFileUtil {
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_file) OVERRIDE;
+      base::FilePath* platform_file) OVERRIDE;
   virtual scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
       FileSystemOperationContext* context,
       const FileSystemURL& root_url,
@@ -58,7 +58,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE LocalFileUtil : public FileSystemFileUtil {
   virtual base::PlatformFileError GetLocalFilePath(
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
-      FilePath* local_file_path) OVERRIDE;
+      base::FilePath* local_file_path) OVERRIDE;
   virtual base::PlatformFileError Touch(
       FileSystemOperationContext* context,
       const FileSystemURL& url,
@@ -75,7 +75,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE LocalFileUtil : public FileSystemFileUtil {
       bool copy) OVERRIDE;
   virtual base::PlatformFileError CopyInForeignFile(
       FileSystemOperationContext* context,
-      const FilePath& src_file_path,
+      const base::FilePath& src_file_path,
       const FileSystemURL& dest_url) OVERRIDE;
   virtual base::PlatformFileError DeleteFile(
       FileSystemOperationContext* context,
@@ -87,7 +87,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE LocalFileUtil : public FileSystemFileUtil {
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path,
+      base::FilePath* platform_path,
       SnapshotFilePolicy* snapshot_policy) OVERRIDE;
 
  private:
diff --git a/webkit/fileapi/local_file_util_unittest.cc b/webkit/fileapi/local_file_util_unittest.cc
index 72c9ecb97cc485..fc3175a531a6ff 100644
--- a/webkit/fileapi/local_file_util_unittest.cc
+++ b/webkit/fileapi/local_file_util_unittest.cc
@@ -51,7 +51,7 @@ class LocalFileUtilTest : public testing::Test {
     return test_helper_.CreateURLFromUTF8(file_name);
   }
 
-  FilePath LocalPath(const char *file_name) {
+  base::FilePath LocalPath(const char *file_name) {
     return test_helper_.GetLocalPathFromASCII(file_name);
   }
 
diff --git a/webkit/fileapi/media/device_media_file_util.cc b/webkit/fileapi/media/device_media_file_util.cc
index a5db4a86a46ef0..b1f037cd99df23 100644
--- a/webkit/fileapi/media/device_media_file_util.cc
+++ b/webkit/fileapi/media/device_media_file_util.cc
@@ -22,7 +22,7 @@ namespace fileapi {
 
 namespace {
 
-const FilePath::CharType kDeviceMediaFileUtilTempDir[] =
+const base::FilePath::CharType kDeviceMediaFileUtilTempDir[] =
     FILE_PATH_LITERAL("DeviceMediaFileSystem");
 
 MTPDeviceDelegate* GetMTPDeviceDelegate(FileSystemOperationContext* context) {
@@ -33,7 +33,7 @@ MTPDeviceDelegate* GetMTPDeviceDelegate(FileSystemOperationContext* context) {
 
 }  // namespace
 
-DeviceMediaFileUtil::DeviceMediaFileUtil(const FilePath& profile_path)
+DeviceMediaFileUtil::DeviceMediaFileUtil(const base::FilePath& profile_path)
     : profile_path_(profile_path) {
 }
 
@@ -70,7 +70,7 @@ PlatformFileError DeviceMediaFileUtil::GetFileInfo(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     PlatformFileInfo* file_info,
-    FilePath* platform_path) {
+    base::FilePath* platform_path) {
   MTPDeviceDelegate* delegate = GetMTPDeviceDelegate(context);
   if (!delegate)
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
@@ -104,7 +104,7 @@ DeviceMediaFileUtil::CreateFileEnumerator(
 PlatformFileError DeviceMediaFileUtil::GetLocalFilePath(
     FileSystemOperationContext* context,
     const FileSystemURL& file_system_url,
-    FilePath* local_file_path) {
+    base::FilePath* local_file_path) {
   return base::PLATFORM_FILE_ERROR_SECURITY;
 }
 
@@ -133,7 +133,7 @@ PlatformFileError DeviceMediaFileUtil::CopyOrMoveFile(
 
 PlatformFileError DeviceMediaFileUtil::CopyInForeignFile(
     FileSystemOperationContext* context,
-    const FilePath& src_file_path,
+    const base::FilePath& src_file_path,
     const FileSystemURL& dest_url) {
   return base::PLATFORM_FILE_ERROR_SECURITY;
 }
@@ -154,7 +154,7 @@ base::PlatformFileError DeviceMediaFileUtil::CreateSnapshotFile(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     base::PlatformFileInfo* file_info,
-    FilePath* local_path,
+    base::FilePath* local_path,
     SnapshotFilePolicy* snapshot_policy) {
   DCHECK(file_info);
   DCHECK(local_path);
@@ -167,7 +167,7 @@ base::PlatformFileError DeviceMediaFileUtil::CreateSnapshotFile(
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
 
   // Create a temp file in "profile_path_/kDeviceMediaFileUtilTempDir".
-  FilePath isolated_media_file_system_dir_path =
+  base::FilePath isolated_media_file_system_dir_path =
       profile_path_.Append(kDeviceMediaFileUtilTempDir);
   bool dir_exists = file_util::DirectoryExists(
       isolated_media_file_system_dir_path);
diff --git a/webkit/fileapi/media/device_media_file_util.h b/webkit/fileapi/media/device_media_file_util.h
index bd6bb802260eb0..efe85c74ad049f 100644
--- a/webkit/fileapi/media/device_media_file_util.h
+++ b/webkit/fileapi/media/device_media_file_util.h
@@ -22,7 +22,7 @@ class FileSystemOperationContext;
 class WEBKIT_STORAGE_EXPORT_PRIVATE DeviceMediaFileUtil
     : public FileSystemFileUtil {
  public:
-  explicit DeviceMediaFileUtil(const FilePath& profile_path);
+  explicit DeviceMediaFileUtil(const base::FilePath& profile_path);
   virtual ~DeviceMediaFileUtil() {}
 
   // FileSystemFileUtil overrides.
@@ -47,7 +47,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE DeviceMediaFileUtil
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path) OVERRIDE;
+      base::FilePath* platform_path) OVERRIDE;
   virtual scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
       FileSystemOperationContext* context,
       const FileSystemURL& root_url,
@@ -55,7 +55,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE DeviceMediaFileUtil
   virtual base::PlatformFileError GetLocalFilePath(
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
-      FilePath* local_file_path) OVERRIDE;
+      base::FilePath* local_file_path) OVERRIDE;
   virtual base::PlatformFileError Touch(
       FileSystemOperationContext* context,
       const FileSystemURL& url,
@@ -72,7 +72,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE DeviceMediaFileUtil
       bool copy) OVERRIDE;
   virtual base::PlatformFileError CopyInForeignFile(
       FileSystemOperationContext* context,
-      const FilePath& src_file_path,
+      const base::FilePath& src_file_path,
       const FileSystemURL& dest_url) OVERRIDE;
   virtual base::PlatformFileError DeleteFile(
       FileSystemOperationContext* context,
@@ -84,12 +84,12 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE DeviceMediaFileUtil
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path,
+      base::FilePath* platform_path,
       SnapshotFilePolicy* policy) OVERRIDE;
 
  private:
   // Profile path
-  const FilePath profile_path_;
+  const base::FilePath profile_path_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceMediaFileUtil);
 };
diff --git a/webkit/fileapi/media/filtering_file_enumerator.cc b/webkit/fileapi/media/filtering_file_enumerator.cc
index e2916974a2e466..393cfa24c7e8c8 100644
--- a/webkit/fileapi/media/filtering_file_enumerator.cc
+++ b/webkit/fileapi/media/filtering_file_enumerator.cc
@@ -21,8 +21,8 @@ namespace {
 
 // Used to skip the hidden folders and files. Returns true if the file specified
 // by |path| should be skipped.
-bool ShouldSkip(const FilePath& path) {
-  const FilePath& base_name = path.BaseName();
+bool ShouldSkip(const base::FilePath& path) {
+  const base::FilePath& base_name = path.BaseName();
   if (base_name.empty())
     return false;
 
@@ -77,9 +77,9 @@ FilteringFileEnumerator::FilteringFileEnumerator(
 FilteringFileEnumerator::~FilteringFileEnumerator() {
 }
 
-FilePath FilteringFileEnumerator::Next() {
+base::FilePath FilteringFileEnumerator::Next() {
   while (true) {
-    FilePath next = base_enumerator_->Next();
+    base::FilePath next = base_enumerator_->Next();
     if (ShouldSkip(next))
       continue;
 
diff --git a/webkit/fileapi/media/filtering_file_enumerator.h b/webkit/fileapi/media/filtering_file_enumerator.h
index 9e70880d02eb79..accb2b097a130b 100644
--- a/webkit/fileapi/media/filtering_file_enumerator.h
+++ b/webkit/fileapi/media/filtering_file_enumerator.h
@@ -22,7 +22,7 @@ class WEBKIT_STORAGE_EXPORT FilteringFileEnumerator
       MediaPathFilter* filter);
   virtual ~FilteringFileEnumerator();
 
-  virtual FilePath Next() OVERRIDE;
+  virtual base::FilePath Next() OVERRIDE;
   virtual int64 Size() OVERRIDE;
   virtual base::Time LastModifiedTime() OVERRIDE;
   virtual bool IsDirectory() OVERRIDE;
diff --git a/webkit/fileapi/media/media_path_filter.cc b/webkit/fileapi/media/media_path_filter.cc
index ae92c196fb4c1e..c9a0a818319254 100644
--- a/webkit/fileapi/media/media_path_filter.cc
+++ b/webkit/fileapi/media/media_path_filter.cc
@@ -14,7 +14,7 @@ namespace fileapi {
 
 namespace {
 
-const FilePath::CharType* const kExtraSupportedExtensions[] = {
+const base::FilePath::CharType* const kExtraSupportedExtensions[] = {
   FILE_PATH_LITERAL("3gp"),
   FILE_PATH_LITERAL("3gpp"),
   FILE_PATH_LITERAL("avi"),
@@ -27,7 +27,7 @@ const FilePath::CharType* const kExtraSupportedExtensions[] = {
   FILE_PATH_LITERAL("wmv"),
 };
 
-bool IsUnsupportedExtension(const FilePath::StringType& extension) {
+bool IsUnsupportedExtension(const base::FilePath::StringType& extension) {
   std::string mime_type;
   return !net::GetMimeTypeFromExtension(extension, &mime_type) ||
       !net::IsSupportedMimeType(mime_type);
@@ -42,7 +42,7 @@ MediaPathFilter::MediaPathFilter()
 MediaPathFilter::~MediaPathFilter() {
 }
 
-bool MediaPathFilter::Match(const FilePath& path) {
+bool MediaPathFilter::Match(const base::FilePath& path) {
   EnsureInitialized();
   return std::binary_search(media_file_extensions_.begin(),
                             media_file_extensions_.end(),
@@ -73,7 +73,7 @@ void MediaPathFilter::EnsureInitialized() {
 
   for (MediaFileExtensionList::iterator itr = media_file_extensions_.begin();
        itr != media_file_extensions_.end(); ++itr)
-    *itr = FilePath::kExtensionSeparator + *itr;
+    *itr = base::FilePath::kExtensionSeparator + *itr;
   std::sort(media_file_extensions_.begin(), media_file_extensions_.end());
 
   initialized_ = true;
diff --git a/webkit/fileapi/media/media_path_filter.h b/webkit/fileapi/media/media_path_filter.h
index 9079b8def6cfb8..694be4ea76dd4c 100644
--- a/webkit/fileapi/media/media_path_filter.h
+++ b/webkit/fileapi/media/media_path_filter.h
@@ -11,7 +11,9 @@
 #include "base/synchronization/lock.h"
 #include "webkit/storage/webkit_storage_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace fileapi {
 
@@ -21,10 +23,10 @@ class WEBKIT_STORAGE_EXPORT MediaPathFilter {
  public:
   MediaPathFilter();
   ~MediaPathFilter();
-  bool Match(const FilePath& path);
+  bool Match(const base::FilePath& path);
 
  private:
-  typedef std::vector<FilePath::StringType> MediaFileExtensionList;
+  typedef std::vector<base::FilePath::StringType> MediaFileExtensionList;
 
   void EnsureInitialized();
 
diff --git a/webkit/fileapi/media/mtp_device_delegate.h b/webkit/fileapi/media/mtp_device_delegate.h
index 793f46c37c83da..a5e89acdff865b 100644
--- a/webkit/fileapi/media/mtp_device_delegate.h
+++ b/webkit/fileapi/media/mtp_device_delegate.h
@@ -9,9 +9,8 @@
 #include "base/platform_file.h"
 #include "webkit/fileapi/file_system_file_util.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 class Time;
 }
@@ -26,7 +25,7 @@ class MTPDeviceDelegate {
  public:
   // Returns information about the given file path.
   virtual base::PlatformFileError GetFileInfo(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       base::PlatformFileInfo* file_info) = 0;
 
   // Returns a pointer to a new instance of AbstractFileEnumerator to enumerate
@@ -34,15 +33,15 @@ class MTPDeviceDelegate {
   // caller, and its lifetime should not extend past when the current call
   // returns to the main media task runner thread.
   virtual scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
-      CreateFileEnumerator(const FilePath& root,
+      CreateFileEnumerator(const base::FilePath& root,
                            bool recursive) = 0;
 
   // Updates the temporary snapshot file contents given by |local_path| with
   // media file contents given by |device_file_path| and also returns the
   // metadata of the temporary file.
   virtual base::PlatformFileError CreateSnapshotFile(
-      const FilePath& device_file_path,
-      const FilePath& local_path,
+      const base::FilePath& device_file_path,
+      const base::FilePath& local_path,
       base::PlatformFileInfo* file_info) = 0;
 
   // Called when the
diff --git a/webkit/fileapi/media/mtp_device_map_service.cc b/webkit/fileapi/media/mtp_device_map_service.cc
index 73160687d8c056..758a913e817b83 100644
--- a/webkit/fileapi/media/mtp_device_map_service.cc
+++ b/webkit/fileapi/media/mtp_device_map_service.cc
@@ -26,7 +26,7 @@ MTPDeviceMapService* MTPDeviceMapService::GetInstance() {
 }
 
 void MTPDeviceMapService::AddDelegate(
-    const FilePath::StringType& device_location,
+    const base::FilePath::StringType& device_location,
     MTPDeviceDelegate* delegate) {
   DCHECK(delegate);
   DCHECK(!device_location.empty());
@@ -38,7 +38,7 @@ void MTPDeviceMapService::AddDelegate(
 }
 
 void MTPDeviceMapService::RemoveDelegate(
-    const FilePath::StringType& device_location) {
+    const base::FilePath::StringType& device_location) {
   base::AutoLock lock(lock_);
   DelegateMap::iterator it = delegate_map_.find(device_location);
   DCHECK(it != delegate_map_.end());
@@ -48,13 +48,13 @@ void MTPDeviceMapService::RemoveDelegate(
 
 MTPDeviceDelegate* MTPDeviceMapService::GetMTPDeviceDelegate(
     const std::string& filesystem_id) {
-  FilePath device_path;
+  base::FilePath device_path;
   if (!IsolatedContext::GetInstance()->GetRegisteredPath(filesystem_id,
                                                          &device_path)) {
     return NULL;
   }
 
-  const FilePath::StringType& device_location = device_path.value();
+  const base::FilePath::StringType& device_location = device_path.value();
   DCHECK(!device_location.empty());
 
   base::AutoLock lock(lock_);
diff --git a/webkit/fileapi/media/mtp_device_map_service.h b/webkit/fileapi/media/mtp_device_map_service.h
index 686d1cb85c1dcd..69da393b338e17 100644
--- a/webkit/fileapi/media/mtp_device_map_service.h
+++ b/webkit/fileapi/media/mtp_device_map_service.h
@@ -26,13 +26,13 @@ class WEBKIT_STORAGE_EXPORT MTPDeviceMapService {
   // Adds the MTP device delegate to the map service. |device_location|
   // specifies the mount location of the MTP device.
   // Called on a media task runner thread.
-  void AddDelegate(const FilePath::StringType& device_location,
+  void AddDelegate(const base::FilePath::StringType& device_location,
                    MTPDeviceDelegate* delegate);
 
   // Removes the MTP device delegate from the map service. |device_location|
   // specifies the mount location of the MTP device.
   // Called on the UI thread.
-  void RemoveDelegate(const FilePath::StringType& device_location);
+  void RemoveDelegate(const base::FilePath::StringType& device_location);
 
   // Gets the media device delegate associated with |filesystem_id|.
   // Return NULL if the |filesystem_id| is no longer valid (e.g. because the
@@ -47,7 +47,7 @@ class WEBKIT_STORAGE_EXPORT MTPDeviceMapService {
 
   // Mapping of device_location and MTPDeviceDelegate* object. It is safe to
   // store and access the raw pointer. This class operates on the IO thread.
-  typedef std::map<FilePath::StringType, MTPDeviceDelegate*> DelegateMap;
+  typedef std::map<base::FilePath::StringType, MTPDeviceDelegate*> DelegateMap;
 
   // Get access to this class using GetInstance() method.
   MTPDeviceMapService();
diff --git a/webkit/fileapi/media/native_media_file_util.cc b/webkit/fileapi/media/native_media_file_util.cc
index 6f7c53c4c97c80..115278c5b7c617 100644
--- a/webkit/fileapi/media/native_media_file_util.cc
+++ b/webkit/fileapi/media/native_media_file_util.cc
@@ -31,7 +31,7 @@ PlatformFileError NativeMediaFileUtil::CreateOrOpen(
 PlatformFileError NativeMediaFileUtil::EnsureFileExists(
     FileSystemOperationContext* context,
     const FileSystemURL& url, bool* created) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetFilteredLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -55,7 +55,7 @@ PlatformFileError NativeMediaFileUtil::Touch(
     const FileSystemURL& url,
     const base::Time& last_access_time,
     const base::Time& last_modified_time) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetFilteredLocalFilePathForExistingFileOrDirectory(
       context,
       url,
@@ -71,7 +71,7 @@ PlatformFileError NativeMediaFileUtil::Truncate(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     int64 length) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetFilteredLocalFilePathForExistingFileOrDirectory(
       context,
       url,
@@ -88,7 +88,7 @@ PlatformFileError NativeMediaFileUtil::CopyOrMoveFile(
     const FileSystemURL& src_url,
     const FileSystemURL& dest_url,
     bool copy) {
-  FilePath src_file_path;
+  base::FilePath src_file_path;
   PlatformFileError error =
       GetFilteredLocalFilePathForExistingFileOrDirectory(
           context, src_url,
@@ -99,7 +99,7 @@ PlatformFileError NativeMediaFileUtil::CopyOrMoveFile(
   if (NativeFileUtil::DirectoryExists(src_file_path))
     return base::PLATFORM_FILE_ERROR_NOT_A_FILE;
 
-  FilePath dest_file_path;
+  base::FilePath dest_file_path;
   error = GetLocalFilePath(context, dest_url, &dest_file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -118,12 +118,12 @@ PlatformFileError NativeMediaFileUtil::CopyOrMoveFile(
 
 PlatformFileError NativeMediaFileUtil::CopyInForeignFile(
     FileSystemOperationContext* context,
-    const FilePath& src_file_path,
+    const base::FilePath& src_file_path,
     const FileSystemURL& dest_url) {
   if (src_file_path.empty())
     return base::PLATFORM_FILE_ERROR_INVALID_OPERATION;
 
-  FilePath dest_file_path;
+  base::FilePath dest_file_path;
   PlatformFileError error =
       GetFilteredLocalFilePath(context, dest_url, &dest_file_path);
   if (error != base::PLATFORM_FILE_OK)
@@ -134,7 +134,7 @@ PlatformFileError NativeMediaFileUtil::CopyInForeignFile(
 PlatformFileError NativeMediaFileUtil::DeleteFile(
     FileSystemOperationContext* context,
     const FileSystemURL& url) {
-  FilePath file_path;
+  base::FilePath file_path;
   PlatformFileError error = GetLocalFilePath(context, url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
     return error;
@@ -153,7 +153,7 @@ PlatformFileError NativeMediaFileUtil::GetFileInfo(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     PlatformFileInfo* file_info,
-    FilePath* platform_path) {
+    base::FilePath* platform_path) {
   DCHECK(context);
   DCHECK(context->media_path_filter());
   DCHECK(file_info);
@@ -174,8 +174,8 @@ PlatformFileError NativeMediaFileUtil::GetFileInfo(
 PlatformFileError NativeMediaFileUtil::GetFilteredLocalFilePath(
     FileSystemOperationContext* context,
     const FileSystemURL& file_system_url,
-    FilePath* local_file_path) {
-  FilePath file_path;
+    base::FilePath* local_file_path) {
+  base::FilePath file_path;
   PlatformFileError error =
       IsolatedFileUtil::GetLocalFilePath(context, file_system_url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
@@ -192,8 +192,8 @@ NativeMediaFileUtil::GetFilteredLocalFilePathForExistingFileOrDirectory(
     FileSystemOperationContext* context,
     const FileSystemURL& file_system_url,
     PlatformFileError failure_error,
-    FilePath* local_file_path) {
-  FilePath file_path;
+    base::FilePath* local_file_path) {
+  base::FilePath file_path;
   PlatformFileError error =
       GetLocalFilePath(context, file_system_url, &file_path);
   if (error != base::PLATFORM_FILE_OK)
diff --git a/webkit/fileapi/media/native_media_file_util.h b/webkit/fileapi/media/native_media_file_util.h
index 97b0999639d4f7..b1e35733d850b9 100644
--- a/webkit/fileapi/media/native_media_file_util.h
+++ b/webkit/fileapi/media/native_media_file_util.h
@@ -48,7 +48,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE NativeMediaFileUtil
       bool copy) OVERRIDE;
   virtual base::PlatformFileError CopyInForeignFile(
         FileSystemOperationContext* context,
-        const FilePath& src_file_path,
+        const base::FilePath& src_file_path,
         const FileSystemURL& dest_url) OVERRIDE;
   virtual base::PlatformFileError DeleteFile(
       FileSystemOperationContext* context,
@@ -57,7 +57,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE NativeMediaFileUtil
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path) OVERRIDE;
+      base::FilePath* platform_path) OVERRIDE;
 
  private:
   // Like GetLocalFilePath(), but always take media_path_filter() into
@@ -66,7 +66,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE NativeMediaFileUtil
   base::PlatformFileError GetFilteredLocalFilePath(
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
-      FilePath* local_file_path);
+      base::FilePath* local_file_path);
 
   // Like GetLocalFilePath(), but if the file does not exist, then return
   // |failure_error|.
@@ -78,7 +78,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE NativeMediaFileUtil
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
       base::PlatformFileError failure_error,
-      FilePath* local_file_path);
+      base::FilePath* local_file_path);
 
   DISALLOW_COPY_AND_ASSIGN(NativeMediaFileUtil);
 };
diff --git a/webkit/fileapi/media/native_media_file_util_unittest.cc b/webkit/fileapi/media/native_media_file_util_unittest.cc
index 8fab4d3ba385b3..f98379b3c29e74 100644
--- a/webkit/fileapi/media/native_media_file_util_unittest.cc
+++ b/webkit/fileapi/media/native_media_file_util_unittest.cc
@@ -32,7 +32,7 @@ namespace {
 typedef FileSystemOperation::FileEntryList FileEntryList;
 
 struct FilteringTestCase {
-  const FilePath::CharType* path;
+  const base::FilePath::CharType* path;
   bool is_directory;
   bool visible;
 };
@@ -62,13 +62,13 @@ void ExpectMetadataEqHelper(const std::string& test_name,
                             bool expected_is_directory,
                             base::PlatformFileError actual,
                             const base::PlatformFileInfo& file_info,
-                            const FilePath& /*platform_path*/) {
+                            const base::FilePath& /*platform_path*/) {
   EXPECT_EQ(expected, actual) << test_name;
   if (actual == base::PLATFORM_FILE_OK)
     EXPECT_EQ(expected_is_directory, file_info.is_directory) << test_name;
 }
 
-void DidReadDirectory(std::set<FilePath::StringType>* content,
+void DidReadDirectory(std::set<base::FilePath::StringType>* content,
                       bool* completed,
                       base::PlatformFileError error,
                       const FileEntryList& file_list,
@@ -80,11 +80,11 @@ void DidReadDirectory(std::set<FilePath::StringType>* content,
     EXPECT_TRUE(content->insert(itr->name).second);
 }
 
-void PopulateDirectoryWithTestCases(const FilePath& dir,
+void PopulateDirectoryWithTestCases(const base::FilePath& dir,
                                     const FilteringTestCase* test_cases,
                                     size_t n) {
   for (size_t i = 0; i < n; ++i) {
-    FilePath path = dir.Append(test_cases[i].path);
+    base::FilePath path = dir.Append(test_cases[i].path);
     if (test_cases[i].is_directory) {
       ASSERT_TRUE(file_util::CreateDirectory(path));
     } else {
@@ -138,7 +138,7 @@ class NativeMediaFileUtilTest : public testing::Test {
     return file_system_context_.get();
   }
 
-  FileSystemURL CreateURL(const FilePath::CharType* test_case_path) {
+  FileSystemURL CreateURL(const base::FilePath::CharType* test_case_path) {
     return file_system_context_->CreateCrackedFileSystemURL(
         origin(),
         fileapi::kFileSystemTypeIsolated,
@@ -149,14 +149,14 @@ class NativeMediaFileUtilTest : public testing::Test {
     return IsolatedContext::GetInstance();
   }
 
-  FilePath root_path() {
+  base::FilePath root_path() {
     return data_dir_.path().Append(FPL("Media Directory"));
   }
 
-  FilePath GetVirtualPath(const FilePath::CharType* test_case_path) {
-    return FilePath::FromUTF8Unsafe(filesystem_id_).
+  base::FilePath GetVirtualPath(const base::FilePath::CharType* test_case_path) {
+    return base::FilePath::FromUTF8Unsafe(filesystem_id_).
                Append(FPL("Media Directory")).
-               Append(FilePath(test_case_path));
+               Append(base::FilePath(test_case_path));
   }
 
   FileSystemFileUtil* file_util() {
@@ -219,7 +219,7 @@ TEST_F(NativeMediaFileUtilTest, ReadDirectoryFiltering) {
                                  kFilteringTestCases,
                                  arraysize(kFilteringTestCases));
 
-  std::set<FilePath::StringType> content;
+  std::set<base::FilePath::StringType> content;
   FileSystemURL url = CreateURL(FPL(""));
   bool completed = false;
   NewOperation(url)->ReadDirectory(
@@ -229,9 +229,9 @@ TEST_F(NativeMediaFileUtilTest, ReadDirectoryFiltering) {
   EXPECT_EQ(5u, content.size());
 
   for (size_t i = 0; i < arraysize(kFilteringTestCases); ++i) {
-    FilePath::StringType name =
-        FilePath(kFilteringTestCases[i].path).BaseName().value();
-    std::set<FilePath::StringType>::const_iterator found = content.find(name);
+    base::FilePath::StringType name =
+        base::FilePath(kFilteringTestCases[i].path).BaseName().value();
+    std::set<base::FilePath::StringType>::const_iterator found = content.find(name);
     EXPECT_EQ(kFilteringTestCases[i].visible, found != content.end());
   }
 }
@@ -267,7 +267,7 @@ TEST_F(NativeMediaFileUtilTest, CreateFileAndCreateDirectoryFiltering) {
 }
 
 TEST_F(NativeMediaFileUtilTest, CopySourceFiltering) {
-  FilePath dest_path = root_path().AppendASCII("dest");
+  base::FilePath dest_path = root_path().AppendASCII("dest");
   FileSystemURL dest_url = CreateURL(FPL("dest"));
 
   // Run the loop twice. The first run has no source files. The second run does.
@@ -320,7 +320,7 @@ TEST_F(NativeMediaFileUtilTest, CopyDestFiltering) {
     }
 
     // Always create a dummy source data file.
-    FilePath src_path = root_path().AppendASCII("foo.jpg");
+    base::FilePath src_path = root_path().AppendASCII("foo.jpg");
     FileSystemURL src_url = CreateURL(FPL("foo.jpg"));
     static const char kDummyData[] = "dummy";
     ASSERT_TRUE(file_util::WriteFile(src_path, kDummyData, strlen(kDummyData)));
@@ -372,7 +372,7 @@ TEST_F(NativeMediaFileUtilTest, CopyDestFiltering) {
 }
 
 TEST_F(NativeMediaFileUtilTest, MoveSourceFiltering) {
-  FilePath dest_path = root_path().AppendASCII("dest");
+  base::FilePath dest_path = root_path().AppendASCII("dest");
   FileSystemURL dest_url = CreateURL(FPL("dest"));
 
   // Run the loop twice. The first run has no source files. The second run does.
@@ -434,7 +434,7 @@ TEST_F(NativeMediaFileUtilTest, MoveDestFiltering) {
       }
 
       // Create the source file for every test case because it might get moved.
-      FilePath src_path = root_path().AppendASCII("foo.jpg");
+      base::FilePath src_path = root_path().AppendASCII("foo.jpg");
       FileSystemURL src_url = CreateURL(FPL("foo.jpg"));
       static const char kDummyData[] = "dummy";
       ASSERT_TRUE(
diff --git a/webkit/fileapi/mount_points.cc b/webkit/fileapi/mount_points.cc
index d754b25b6182e0..fbd881d965ee42 100644
--- a/webkit/fileapi/mount_points.cc
+++ b/webkit/fileapi/mount_points.cc
@@ -8,7 +8,7 @@ namespace fileapi {
 
 MountPoints::MountPointInfo::MountPointInfo() {}
 MountPoints::MountPointInfo::MountPointInfo(
-    const std::string& name, const FilePath& path)
+    const std::string& name, const base::FilePath& path)
     : name(name), path(path) {}
 
 }  // namespace fileapi
diff --git a/webkit/fileapi/mount_points.h b/webkit/fileapi/mount_points.h
index 27df0f279ab17c..30779bbf090527 100644
--- a/webkit/fileapi/mount_points.h
+++ b/webkit/fileapi/mount_points.h
@@ -26,7 +26,7 @@ class WEBKIT_STORAGE_EXPORT MountPoints {
  public:
   struct WEBKIT_STORAGE_EXPORT MountPointInfo {
     MountPointInfo();
-    MountPointInfo(const std::string& name, const FilePath& path);
+    MountPointInfo(const std::string& name, const base::FilePath& path);
 
     // The name to be used to register the path. The registered file can
     // be referred by a virtual path /<filesystem_id>/<name>.
@@ -34,7 +34,7 @@ class WEBKIT_STORAGE_EXPORT MountPoints {
     std::string name;
 
     // The path of the file.
-    FilePath path;
+    base::FilePath path;
 
     // For STL operation.
     bool operator<(const MountPointInfo& that) const {
@@ -65,12 +65,12 @@ class WEBKIT_STORAGE_EXPORT MountPoints {
   virtual FileSystemURL CreateCrackedFileSystemURL(
       const GURL& origin,
       fileapi::FileSystemType type,
-      const FilePath& path) const = 0;
+      const base::FilePath& path) const = 0;
 
   // Returns the mount point root path registered for a given |mount_name|.
   // Returns false if the given |mount_name| is not valid.
   virtual bool GetRegisteredPath(const std::string& mount_name,
-                                 FilePath* path) const = 0;
+                                 base::FilePath* path) const = 0;
 
   // Cracks the given |virtual_path| (which is the path part of a filesystem URL
   // without '/external' or '/isolated' prefix part) and populates the
@@ -83,10 +83,10 @@ class WEBKIT_STORAGE_EXPORT MountPoints {
   // Note that |path| is set to empty paths if the filesystem type is isolated
   // and |virtual_path| has no <relative_path> part (i.e. pointing to the
   // virtual root).
-  virtual bool CrackVirtualPath(const FilePath& virtual_path,
+  virtual bool CrackVirtualPath(const base::FilePath& virtual_path,
                                 std::string* mount_name,
                                 FileSystemType* type,
-                                FilePath* path) const = 0;
+                                base::FilePath* path) const = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MountPoints);
diff --git a/webkit/fileapi/native_file_util.cc b/webkit/fileapi/native_file_util.cc
index 7ee3b04b861354..a7942501b194f8 100644
--- a/webkit/fileapi/native_file_util.cc
+++ b/webkit/fileapi/native_file_util.cc
@@ -16,7 +16,7 @@ namespace {
 // Returns true on success, or false otherwise.
 //
 // TODO(benchan): Find a better place outside webkit to host this function.
-bool SetPlatformSpecificDirectoryPermissions(const FilePath& dir_path) {
+bool SetPlatformSpecificDirectoryPermissions(const base::FilePath& dir_path) {
 #if defined(OS_CHROMEOS)
     // System daemons on Chrome OS may run as a user different than the Chrome
     // process but need to access files under the directories created here.
@@ -38,7 +38,7 @@ using base::PlatformFileError;
 
 class NativeFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
  public:
-  NativeFileEnumerator(const FilePath& root_path,
+  NativeFileEnumerator(const base::FilePath& root_path,
                        bool recursive,
                        int file_type)
     : file_enum_(root_path, recursive, file_type) {
@@ -49,7 +49,7 @@ class NativeFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
 
   ~NativeFileEnumerator() {}
 
-  virtual FilePath Next() OVERRIDE;
+  virtual base::FilePath Next() OVERRIDE;
   virtual int64 Size() OVERRIDE;
   virtual base::Time LastModifiedTime() OVERRIDE;
   virtual bool IsDirectory() OVERRIDE;
@@ -59,8 +59,8 @@ class NativeFileEnumerator : public FileSystemFileUtil::AbstractFileEnumerator {
   file_util::FileEnumerator::FindInfo file_util_info_;
 };
 
-FilePath NativeFileEnumerator::Next() {
-  FilePath rv = file_enum_.Next();
+base::FilePath NativeFileEnumerator::Next() {
+  base::FilePath rv = file_enum_.Next();
   if (!rv.empty())
     file_enum_.GetFindInfo(&file_util_info_);
   return rv;
@@ -79,7 +79,7 @@ bool NativeFileEnumerator::IsDirectory() {
 }
 
 PlatformFileError NativeFileUtil::CreateOrOpen(
-    const FilePath& path, int file_flags,
+    const base::FilePath& path, int file_flags,
     PlatformFile* file_handle, bool* created) {
   if (!file_util::DirectoryExists(path.DirName())) {
     // If its parent does not exist, should return NOT_FOUND error.
@@ -98,7 +98,7 @@ PlatformFileError NativeFileUtil::Close(PlatformFile file_handle) {
 }
 
 PlatformFileError NativeFileUtil::EnsureFileExists(
-    const FilePath& path,
+    const base::FilePath& path,
     bool* created) {
   if (!file_util::DirectoryExists(path.DirName()))
     // If its parent does not exist, should return NOT_FOUND error.
@@ -122,7 +122,7 @@ PlatformFileError NativeFileUtil::EnsureFileExists(
 }
 
 PlatformFileError NativeFileUtil::CreateDirectory(
-    const FilePath& path,
+    const base::FilePath& path,
     bool exclusive,
     bool recursive) {
   // If parent dir of file doesn't exist.
@@ -147,7 +147,7 @@ PlatformFileError NativeFileUtil::CreateDirectory(
 }
 
 PlatformFileError NativeFileUtil::GetFileInfo(
-    const FilePath& path,
+    const base::FilePath& path,
     base::PlatformFileInfo* file_info) {
   if (!file_util::PathExists(path))
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
@@ -157,7 +157,7 @@ PlatformFileError NativeFileUtil::GetFileInfo(
 }
 
 scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
-    NativeFileUtil::CreateFileEnumerator(const FilePath& root_path,
+    NativeFileUtil::CreateFileEnumerator(const base::FilePath& root_path,
                                          bool recursive) {
   return make_scoped_ptr(new NativeFileEnumerator(
       root_path, recursive,
@@ -167,7 +167,7 @@ scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
 }
 
 PlatformFileError NativeFileUtil::Touch(
-    const FilePath& path,
+    const base::FilePath& path,
     const base::Time& last_access_time,
     const base::Time& last_modified_time) {
   if (!file_util::TouchFile(
@@ -176,7 +176,7 @@ PlatformFileError NativeFileUtil::Touch(
   return base::PLATFORM_FILE_OK;
 }
 
-PlatformFileError NativeFileUtil::Truncate(const FilePath& path, int64 length) {
+PlatformFileError NativeFileUtil::Truncate(const base::FilePath& path, int64 length) {
   PlatformFileError error_code(base::PLATFORM_FILE_ERROR_FAILED);
   PlatformFile file =
       base::CreatePlatformFile(
@@ -194,17 +194,17 @@ PlatformFileError NativeFileUtil::Truncate(const FilePath& path, int64 length) {
   return error_code;
 }
 
-bool NativeFileUtil::PathExists(const FilePath& path) {
+bool NativeFileUtil::PathExists(const base::FilePath& path) {
   return file_util::PathExists(path);
 }
 
-bool NativeFileUtil::DirectoryExists(const FilePath& path) {
+bool NativeFileUtil::DirectoryExists(const base::FilePath& path) {
   return file_util::DirectoryExists(path);
 }
 
 PlatformFileError NativeFileUtil::CopyOrMoveFile(
-    const FilePath& src_path,
-    const FilePath& dest_path,
+    const base::FilePath& src_path,
+    const base::FilePath& dest_path,
     bool copy) {
   base::PlatformFileInfo info;
   base::PlatformFileError error = NativeFileUtil::GetFileInfo(src_path, &info);
@@ -237,7 +237,7 @@ PlatformFileError NativeFileUtil::CopyOrMoveFile(
   return base::PLATFORM_FILE_ERROR_FAILED;
 }
 
-PlatformFileError NativeFileUtil::DeleteFile(const FilePath& path) {
+PlatformFileError NativeFileUtil::DeleteFile(const base::FilePath& path) {
   if (!file_util::PathExists(path))
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
   if (file_util::DirectoryExists(path))
@@ -247,7 +247,7 @@ PlatformFileError NativeFileUtil::DeleteFile(const FilePath& path) {
   return base::PLATFORM_FILE_OK;
 }
 
-PlatformFileError NativeFileUtil::DeleteDirectory(const FilePath& path) {
+PlatformFileError NativeFileUtil::DeleteDirectory(const base::FilePath& path) {
   if (!file_util::PathExists(path))
     return base::PLATFORM_FILE_ERROR_NOT_FOUND;
   if (!file_util::DirectoryExists(path))
diff --git a/webkit/fileapi/native_file_util.h b/webkit/fileapi/native_file_util.h
index 075d27b25289a2..55f3297c87c178 100644
--- a/webkit/fileapi/native_file_util.h
+++ b/webkit/fileapi/native_file_util.h
@@ -33,32 +33,32 @@ namespace fileapi {
 class WEBKIT_STORAGE_EXPORT_PRIVATE NativeFileUtil {
  public:
   static base::PlatformFileError CreateOrOpen(
-      const FilePath& path,
+      const base::FilePath& path,
       int file_flags,
       base::PlatformFile* file_handle,
       bool* created);
   static base::PlatformFileError Close(base::PlatformFile file);
-  static base::PlatformFileError EnsureFileExists(const FilePath& path,
+  static base::PlatformFileError EnsureFileExists(const base::FilePath& path,
                                                   bool* created);
-  static base::PlatformFileError CreateDirectory(const FilePath& path,
+  static base::PlatformFileError CreateDirectory(const base::FilePath& path,
                                                  bool exclusive,
                                                  bool recursive);
-  static base::PlatformFileError GetFileInfo(const FilePath& path,
+  static base::PlatformFileError GetFileInfo(const base::FilePath& path,
                                              base::PlatformFileInfo* file_info);
   static scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
-      CreateFileEnumerator(const FilePath& root_path,
+      CreateFileEnumerator(const base::FilePath& root_path,
                            bool recursive);
-  static base::PlatformFileError Touch(const FilePath& path,
+  static base::PlatformFileError Touch(const base::FilePath& path,
                                        const base::Time& last_access_time,
                                        const base::Time& last_modified_time);
-  static base::PlatformFileError Truncate(const FilePath& path, int64 length);
-  static bool PathExists(const FilePath& path);
-  static bool DirectoryExists(const FilePath& path);
-  static base::PlatformFileError CopyOrMoveFile(const FilePath& src_path,
-                                                const FilePath& dest_path,
+  static base::PlatformFileError Truncate(const base::FilePath& path, int64 length);
+  static bool PathExists(const base::FilePath& path);
+  static bool DirectoryExists(const base::FilePath& path);
+  static base::PlatformFileError CopyOrMoveFile(const base::FilePath& src_path,
+                                                const base::FilePath& dest_path,
                                                 bool copy);
-  static base::PlatformFileError DeleteFile(const FilePath& path);
-  static base::PlatformFileError DeleteDirectory(const FilePath& path);
+  static base::PlatformFileError DeleteFile(const base::FilePath& path);
+  static base::PlatformFileError DeleteDirectory(const base::FilePath& path);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(NativeFileUtil);
diff --git a/webkit/fileapi/obfuscated_file_util.cc b/webkit/fileapi/obfuscated_file_util.cc
index dd75118a978bf7..657eef1077f68b 100644
--- a/webkit/fileapi/obfuscated_file_util.cc
+++ b/webkit/fileapi/obfuscated_file_util.cc
@@ -28,8 +28,8 @@
 
 // Example of various paths:
 //   void ObfuscatedFileUtil::DoSomething(const FileSystemURL& url) {
-//     FilePath virtual_path = url.path();
-//     FilePath local_path = GetLocalFilePath(url);
+//     base::FilePath virtual_path = url.path();
+//     base::FilePath local_path = GetLocalFilePath(url);
 //
 //     NativeFileUtil::DoSomething(local_path);
 //     file_util::DoAnother(local_path);
@@ -47,7 +47,7 @@ const int64 kFlushDelaySeconds = 10 * 60;  // 10 minutes
 void InitFileInfo(
     FileSystemDirectoryDatabase::FileInfo* file_info,
     FileSystemDirectoryDatabase::FileId parent_id,
-    const FilePath::StringType& file_name) {
+    const base::FilePath::StringType& file_name) {
   DCHECK(file_info);
   file_info->parent_id = parent_id;
   file_info->name = file_name;
@@ -55,7 +55,7 @@ void InitFileInfo(
 
 // Costs computed as per crbug.com/86114, based on the LevelDB implementation of
 // path storage under Linux.  It's not clear if that will differ on Windows, on
-// which FilePath uses wide chars [since they're converted to UTF-8 for storage
+// which base::FilePath uses wide chars [since they're converted to UTF-8 for storage
 // anyway], but as long as the cost is high enough that one can't cheat on quota
 // by storing data in paths, it doesn't need to be all that accurate.
 const int64 kPathCreationQuotaCost = 146;  // Bytes per inode, basically.
@@ -91,9 +91,9 @@ void TouchDirectory(FileSystemDirectoryDatabase* db, FileId dir_id) {
     NOTREACHED();
 }
 
-const FilePath::CharType kTemporaryDirectoryName[] = FILE_PATH_LITERAL("t");
-const FilePath::CharType kPersistentDirectoryName[] = FILE_PATH_LITERAL("p");
-const FilePath::CharType kSyncableDirectoryName[] = FILE_PATH_LITERAL("s");
+const base::FilePath::CharType kTemporaryDirectoryName[] = FILE_PATH_LITERAL("t");
+const base::FilePath::CharType kPersistentDirectoryName[] = FILE_PATH_LITERAL("p");
+const base::FilePath::CharType kSyncableDirectoryName[] = FILE_PATH_LITERAL("s");
 
 }  // namespace
 
@@ -116,7 +116,7 @@ class ObfuscatedFileEnumerator
         type_(root_url.type()),
         recursive_(recursive),
         current_file_id_(0) {
-    FilePath root_virtual_path = root_url.path();
+    base::FilePath root_virtual_path = root_url.path();
     FileId file_id;
 
     if (!db_->GetFileWithPath(root_virtual_path, &file_id))
@@ -128,16 +128,16 @@ class ObfuscatedFileEnumerator
 
   virtual ~ObfuscatedFileEnumerator() {}
 
-  virtual FilePath Next() OVERRIDE {
+  virtual base::FilePath Next() OVERRIDE {
     ProcessRecurseQueue();
     if (display_stack_.empty())
-      return FilePath();
+      return base::FilePath();
 
     current_file_id_ = display_stack_.back();
     display_stack_.pop_back();
 
     FileInfo file_info;
-    FilePath platform_file_path;
+    base::FilePath platform_file_path;
     base::PlatformFileError error =
         obfuscated_file_util_->GetFileInfoInternal(
             db_, context_, origin_, type_, current_file_id_,
@@ -145,7 +145,7 @@ class ObfuscatedFileEnumerator
     if (error != base::PLATFORM_FILE_OK)
       return Next();
 
-    FilePath virtual_path =
+    base::FilePath virtual_path =
         current_parent_virtual_path_.Append(file_info.name);
     if (recursive_ && file_info.is_directory()) {
       FileRecord record = { current_file_id_, virtual_path };
@@ -172,7 +172,7 @@ class ObfuscatedFileEnumerator
 
   struct FileRecord {
     FileId file_id;
-    FilePath virtual_path;
+    base::FilePath virtual_path;
   };
 
   void ProcessRecurseQueue() {
@@ -196,7 +196,7 @@ class ObfuscatedFileEnumerator
 
   std::queue<FileRecord> recurse_queue_;
   std::vector<FileId> display_stack_;
-  FilePath current_parent_virtual_path_;
+  base::FilePath current_parent_virtual_path_;
 
   FileId current_file_id_;
   base::PlatformFileInfo current_platform_file_info_;
@@ -208,7 +208,7 @@ class ObfuscatedOriginEnumerator
   typedef FileSystemOriginDatabase::OriginRecord OriginRecord;
   ObfuscatedOriginEnumerator(
       FileSystemOriginDatabase* origin_database,
-      const FilePath& base_file_path)
+      const base::FilePath& base_file_path)
       : base_file_path_(base_file_path) {
     if (origin_database)
       origin_database->ListAllOrigins(&origins_);
@@ -231,24 +231,24 @@ class ObfuscatedOriginEnumerator
   virtual bool HasFileSystemType(FileSystemType type) const OVERRIDE {
     if (current_.path.empty())
       return false;
-    FilePath::StringType type_string =
+    base::FilePath::StringType type_string =
         ObfuscatedFileUtil::GetDirectoryNameForType(type);
     if (type_string.empty()) {
       NOTREACHED();
       return false;
     }
-    FilePath path = base_file_path_.Append(current_.path).Append(type_string);
+    base::FilePath path = base_file_path_.Append(current_.path).Append(type_string);
     return file_util::DirectoryExists(path);
   }
 
  private:
   std::vector<OriginRecord> origins_;
   OriginRecord current_;
-  FilePath base_file_path_;
+  base::FilePath base_file_path_;
 };
 
 ObfuscatedFileUtil::ObfuscatedFileUtil(
-    const FilePath& file_system_directory)
+    const base::FilePath& file_system_directory)
     : file_system_directory_(file_system_directory) {
 }
 
@@ -285,7 +285,7 @@ PlatformFileError ObfuscatedFileUtil::CreateOrOpen(
     if (!AllocateQuota(context, growth))
       return base::PLATFORM_FILE_ERROR_NO_SPACE;
     PlatformFileError error = CreateFile(
-        context, FilePath(),
+        context, base::FilePath(),
         url.origin(), url.type(), &file_info,
         file_flags, file_handle);
     if (created && base::PLATFORM_FILE_OK == error) {
@@ -301,7 +301,7 @@ PlatformFileError ObfuscatedFileUtil::CreateOrOpen(
     return base::PLATFORM_FILE_ERROR_EXISTS;
 
   base::PlatformFileInfo platform_file_info;
-  FilePath local_path;
+  base::FilePath local_path;
   FileInfo file_info;
   base::PlatformFileError error = GetFileInfoInternal(
       db, context, url.origin(), url.type(), file_id,
@@ -378,7 +378,7 @@ PlatformFileError ObfuscatedFileUtil::EnsureFileExists(
   if (!AllocateQuota(context, growth))
     return base::PLATFORM_FILE_ERROR_NO_SPACE;
   PlatformFileError error = CreateFile(
-      context, FilePath(), url.origin(), url.type(), &file_info, 0, NULL);
+      context, base::FilePath(), url.origin(), url.type(), &file_info, 0, NULL);
   if (created && base::PLATFORM_FILE_OK == error) {
     *created = true;
     UpdateUsage(context, url, growth);
@@ -421,12 +421,12 @@ PlatformFileError ObfuscatedFileUtil::CreateDirectory(
     return base::PLATFORM_FILE_OK;
   }
 
-  std::vector<FilePath::StringType> components;
+  std::vector<base::FilePath::StringType> components;
   VirtualPath::GetComponents(url.path(), &components);
   FileId parent_id = 0;
   size_t index;
   for (index = 0; index < components.size(); ++index) {
-    FilePath::StringType name = components[index];
+    base::FilePath::StringType name = components[index];
     if (name == FILE_PATH_LITERAL("/"))
       continue;
     if (!db->GetChildWithName(parent_id, name, &parent_id))
@@ -464,7 +464,7 @@ PlatformFileError ObfuscatedFileUtil::GetFileInfo(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     base::PlatformFileInfo* file_info,
-    FilePath* platform_file_path) {
+    base::FilePath* platform_file_path) {
   FileSystemDirectoryDatabase* db = GetDirectoryDatabase(
       url.origin(), url.type(), false);
   if (!db)
@@ -498,7 +498,7 @@ scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
 PlatformFileError ObfuscatedFileUtil::GetLocalFilePath(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
-    FilePath* local_path) {
+    base::FilePath* local_path) {
   FileSystemDirectoryDatabase* db = GetDirectoryDatabase(
       url.origin(), url.type(), false);
   if (!db)
@@ -543,7 +543,7 @@ PlatformFileError ObfuscatedFileUtil::Touch(
       return base::PLATFORM_FILE_ERROR_FAILED;
     return base::PLATFORM_FILE_OK;
   }
-  FilePath local_path = DataPathToLocalPath(
+  base::FilePath local_path = DataPathToLocalPath(
       url.origin(), url.type(), file_info.data_path);
   return NativeFileUtil::Touch(
       local_path, last_access_time, last_modified_time);
@@ -554,7 +554,7 @@ PlatformFileError ObfuscatedFileUtil::Truncate(
     const FileSystemURL& url,
     int64 length) {
   base::PlatformFileInfo file_info;
-  FilePath local_path;
+  base::FilePath local_path;
   base::PlatformFileError error =
       GetFileInfo(context, url, &file_info, &local_path);
   if (error != base::PLATFORM_FILE_OK)
@@ -596,7 +596,7 @@ PlatformFileError ObfuscatedFileUtil::CopyOrMoveFile(
 
   FileInfo src_file_info;
   base::PlatformFileInfo src_platform_file_info;
-  FilePath src_local_path;
+  base::FilePath src_local_path;
   base::PlatformFileError error = GetFileInfoInternal(
       db, context, src_url.origin(), src_url.type(), src_file_id,
       &src_file_info, &src_platform_file_info, &src_local_path);
@@ -607,7 +607,7 @@ PlatformFileError ObfuscatedFileUtil::CopyOrMoveFile(
 
   FileInfo dest_file_info;
   base::PlatformFileInfo dest_platform_file_info;  // overwrite case only
-  FilePath dest_local_path;  // overwrite case only
+  base::FilePath dest_local_path;  // overwrite case only
   if (overwrite) {
     base::PlatformFileError error = GetFileInfoInternal(
         db, context, dest_url.origin(), dest_url.type(), dest_file_id,
@@ -715,7 +715,7 @@ PlatformFileError ObfuscatedFileUtil::CopyOrMoveFile(
 
 PlatformFileError ObfuscatedFileUtil::CopyInForeignFile(
     FileSystemOperationContext* context,
-    const FilePath& src_file_path,
+    const base::FilePath& src_file_path,
     const FileSystemURL& dest_url) {
   FileSystemDirectoryDatabase* db = GetDirectoryDatabase(
       dest_url.origin(), dest_url.type(), true);
@@ -733,7 +733,7 @@ PlatformFileError ObfuscatedFileUtil::CopyInForeignFile(
   FileInfo dest_file_info;
   base::PlatformFileInfo dest_platform_file_info;  // overwrite case only
   if (overwrite) {
-    FilePath dest_local_path;
+    base::FilePath dest_local_path;
     base::PlatformFileError error = GetFileInfoInternal(
         db, context, dest_url.origin(), dest_url.type(), dest_file_id,
         &dest_file_info, &dest_platform_file_info, &dest_local_path);
@@ -766,7 +766,7 @@ PlatformFileError ObfuscatedFileUtil::CopyInForeignFile(
 
   base::PlatformFileError error;
   if (overwrite) {
-    FilePath dest_local_path = DataPathToLocalPath(
+    base::FilePath dest_local_path = DataPathToLocalPath(
         dest_url.origin(), dest_url.type(), dest_file_info.data_path);
     error = NativeFileUtil::CopyOrMoveFile(
         src_file_path, dest_local_path, true);
@@ -805,7 +805,7 @@ PlatformFileError ObfuscatedFileUtil::DeleteFile(
 
   FileInfo file_info;
   base::PlatformFileInfo platform_file_info;
-  FilePath local_path;
+  base::FilePath local_path;
   base::PlatformFileError error = GetFileInfoInternal(
       db, context, url.origin(), url.type(), file_id,
       &file_info, &platform_file_info, &local_path);
@@ -870,7 +870,7 @@ base::PlatformFileError ObfuscatedFileUtil::CreateSnapshotFile(
     FileSystemOperationContext* context,
     const FileSystemURL& url,
     base::PlatformFileInfo* file_info,
-    FilePath* platform_path,
+    base::FilePath* platform_path,
     SnapshotFilePolicy* policy) {
   DCHECK(policy);
   // We're just returning the local file information.
@@ -909,23 +909,23 @@ bool ObfuscatedFileUtil::IsDirectoryEmpty(
   return children.empty();
 }
 
-FilePath ObfuscatedFileUtil::GetDirectoryForOriginAndType(
+base::FilePath ObfuscatedFileUtil::GetDirectoryForOriginAndType(
     const GURL& origin,
     FileSystemType type,
     bool create,
     base::PlatformFileError* error_code) {
-  FilePath origin_dir = GetDirectoryForOrigin(origin, create, error_code);
+  base::FilePath origin_dir = GetDirectoryForOrigin(origin, create, error_code);
   if (origin_dir.empty())
-    return FilePath();
-  FilePath::StringType type_string = GetDirectoryNameForType(type);
+    return base::FilePath();
+  base::FilePath::StringType type_string = GetDirectoryNameForType(type);
   if (type_string.empty()) {
     LOG(WARNING) << "Unknown filesystem type requested:" << type;
 
     if (error_code)
       *error_code = base::PLATFORM_FILE_ERROR_INVALID_URL;
-    return FilePath();
+    return base::FilePath();
   }
-  FilePath path = origin_dir.Append(type_string);
+  base::FilePath path = origin_dir.Append(type_string);
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
   if (!file_util::DirectoryExists(path) &&
       (!create || !file_util::CreateDirectory(path))) {
@@ -942,7 +942,7 @@ FilePath ObfuscatedFileUtil::GetDirectoryForOriginAndType(
 bool ObfuscatedFileUtil::DeleteDirectoryForOriginAndType(
     const GURL& origin, FileSystemType type) {
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath origin_type_path = GetDirectoryForOriginAndType(origin, type, false,
+  base::FilePath origin_type_path = GetDirectoryForOriginAndType(origin, type, false,
                                                            &error);
   if (origin_type_path.empty())
     return true;
@@ -958,7 +958,7 @@ bool ObfuscatedFileUtil::DeleteDirectoryForOriginAndType(
       return false;
   }
 
-  FilePath origin_path = origin_type_path.DirName();
+  base::FilePath origin_path = origin_type_path.DirName();
   DCHECK_EQ(origin_path.value(),
             GetDirectoryForOrigin(origin, false, NULL).value());
 
@@ -992,7 +992,7 @@ bool ObfuscatedFileUtil::DeleteDirectoryForOriginAndType(
 }
 
 // static
-FilePath::StringType ObfuscatedFileUtil::GetDirectoryNameForType(
+base::FilePath::StringType ObfuscatedFileUtil::GetDirectoryNameForType(
     FileSystemType type) {
   switch (type) {
     case kFileSystemTypeTemporary:
@@ -1003,7 +1003,7 @@ FilePath::StringType ObfuscatedFileUtil::GetDirectoryNameForType(
       return kSyncableDirectoryName;
     case kFileSystemTypeUnknown:
     default:
-      return FilePath::StringType();
+      return base::FilePath::StringType();
   }
 }
 
@@ -1032,14 +1032,14 @@ bool ObfuscatedFileUtil::DestroyDirectoryDatabase(
   }
 
   PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath path = GetDirectoryForOriginAndType(origin, type, false, &error);
+  base::FilePath path = GetDirectoryForOriginAndType(origin, type, false, &error);
   if (path.empty() || error == base::PLATFORM_FILE_ERROR_NOT_FOUND)
     return true;
   return FileSystemDirectoryDatabase::DestroyDatabase(path);
 }
 
 // static
-int64 ObfuscatedFileUtil::ComputeFilePathCost(const FilePath& path) {
+int64 ObfuscatedFileUtil::ComputeFilePathCost(const base::FilePath& path) {
   return UsageForPath(VirtualPath::BaseName(path).value().size());
 }
 
@@ -1051,7 +1051,7 @@ PlatformFileError ObfuscatedFileUtil::GetFileInfoInternal(
     FileId file_id,
     FileInfo* local_info,
     base::PlatformFileInfo* file_info,
-    FilePath* platform_file_path) {
+    base::FilePath* platform_file_path) {
   DCHECK(db);
   DCHECK(context);
   DCHECK(file_info);
@@ -1067,13 +1067,13 @@ PlatformFileError ObfuscatedFileUtil::GetFileInfoInternal(
     file_info->is_directory = true;
     file_info->is_symbolic_link = false;
     file_info->last_modified = local_info->modification_time;
-    *platform_file_path = FilePath();
+    *platform_file_path = base::FilePath();
     // We don't fill in ctime or atime.
     return base::PLATFORM_FILE_OK;
   }
   if (local_info->data_path.empty())
     return base::PLATFORM_FILE_ERROR_INVALID_OPERATION;
-  FilePath local_path = DataPathToLocalPath(
+  base::FilePath local_path = DataPathToLocalPath(
       origin, type, local_info->data_path);
   base::PlatformFileError error = NativeFileUtil::GetFileInfo(
       local_path, file_info);
@@ -1095,7 +1095,7 @@ PlatformFileError ObfuscatedFileUtil::GetFileInfoInternal(
 
 PlatformFileError ObfuscatedFileUtil::CreateFile(
     FileSystemOperationContext* context,
-    const FilePath& src_file_path,
+    const base::FilePath& src_file_path,
     const GURL& dest_origin,
     FileSystemType dest_type,
     FileInfo* dest_file_info, int file_flags, PlatformFile* handle) {
@@ -1105,12 +1105,12 @@ PlatformFileError ObfuscatedFileUtil::CreateFile(
       dest_origin, dest_type, true);
 
   PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath root = GetDirectoryForOriginAndType(dest_origin, dest_type, false,
+  base::FilePath root = GetDirectoryForOriginAndType(dest_origin, dest_type, false,
                                                &error);
   if (error != base::PLATFORM_FILE_OK)
     return error;
 
-  FilePath dest_local_path;
+  base::FilePath dest_local_path;
   error = GenerateNewLocalPath(db, context, dest_origin, dest_type,
                                &dest_local_path);
   if (error != base::PLATFORM_FILE_OK)
@@ -1157,7 +1157,7 @@ PlatformFileError ObfuscatedFileUtil::CreateFile(
 
   // This removes the root, including the trailing slash, leaving a relative
   // path.
-  dest_file_info->data_path = FilePath(
+  dest_file_info->data_path = base::FilePath(
       dest_local_path.value().substr(root.value().length() + 1));
 
   FileId file_id;
@@ -1174,12 +1174,12 @@ PlatformFileError ObfuscatedFileUtil::CreateFile(
   return base::PLATFORM_FILE_OK;
 }
 
-FilePath ObfuscatedFileUtil::DataPathToLocalPath(
-    const GURL& origin, FileSystemType type, const FilePath& data_path) {
+base::FilePath ObfuscatedFileUtil::DataPathToLocalPath(
+    const GURL& origin, FileSystemType type, const base::FilePath& data_path) {
   PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath root = GetDirectoryForOriginAndType(origin, type, false, &error);
+  base::FilePath root = GetDirectoryForOriginAndType(origin, type, false, &error);
   if (error != base::PLATFORM_FILE_OK)
-    return FilePath();
+    return base::FilePath();
   return root.Append(data_path);
 }
 
@@ -1202,7 +1202,7 @@ FileSystemDirectoryDatabase* ObfuscatedFileUtil::GetDirectoryDatabase(
   }
 
   PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath path = GetDirectoryForOriginAndType(origin, type, create, &error);
+  base::FilePath path = GetDirectoryForOriginAndType(origin, type, create, &error);
   if (error != base::PLATFORM_FILE_OK) {
     LOG(WARNING) << "Failed to get origin+type directory: " << path.value();
     return NULL;
@@ -1213,7 +1213,7 @@ FileSystemDirectoryDatabase* ObfuscatedFileUtil::GetDirectoryDatabase(
   return database;
 }
 
-FilePath ObfuscatedFileUtil::GetDirectoryForOrigin(
+base::FilePath ObfuscatedFileUtil::GetDirectoryForOrigin(
     const GURL& origin, bool create, base::PlatformFileError* error_code) {
   if (!InitOriginDatabase(create)) {
     if (error_code) {
@@ -1221,30 +1221,30 @@ FilePath ObfuscatedFileUtil::GetDirectoryForOrigin(
           base::PLATFORM_FILE_ERROR_FAILED :
           base::PLATFORM_FILE_ERROR_NOT_FOUND;
     }
-    return FilePath();
+    return base::FilePath();
   }
-  FilePath directory_name;
+  base::FilePath directory_name;
   std::string id = GetOriginIdentifierFromURL(origin);
 
   bool exists_in_db = origin_database_->HasOriginPath(id);
   if (!exists_in_db && !create) {
     if (error_code)
       *error_code = base::PLATFORM_FILE_ERROR_NOT_FOUND;
-    return FilePath();
+    return base::FilePath();
   }
   if (!origin_database_->GetPathForOrigin(id, &directory_name)) {
     if (error_code)
       *error_code = base::PLATFORM_FILE_ERROR_FAILED;
-    return FilePath();
+    return base::FilePath();
   }
 
-  FilePath path = file_system_directory_.Append(directory_name);
+  base::FilePath path = file_system_directory_.Append(directory_name);
   bool exists_in_fs = file_util::DirectoryExists(path);
   if (!exists_in_db && exists_in_fs) {
     if (!file_util::Delete(path, true)) {
       if (error_code)
         *error_code = base::PLATFORM_FILE_ERROR_FAILED;
-      return FilePath();
+      return base::FilePath();
     }
     exists_in_fs = false;
   }
@@ -1255,7 +1255,7 @@ FilePath ObfuscatedFileUtil::GetDirectoryForOrigin(
         *error_code = create ?
             base::PLATFORM_FILE_ERROR_FAILED :
             base::PLATFORM_FILE_ERROR_NOT_FOUND;
-      return FilePath();
+      return base::FilePath();
     }
   }
 
@@ -1308,15 +1308,15 @@ PlatformFileError ObfuscatedFileUtil::GenerateNewLocalPath(
     FileSystemOperationContext* context,
     const GURL& origin,
     FileSystemType type,
-    FilePath* local_path) {
+    base::FilePath* local_path) {
   DCHECK(local_path);
   int64 number;
   if (!db || !db->GetNextInteger(&number))
     return base::PLATFORM_FILE_ERROR_FAILED;
 
   PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath new_local_path = GetDirectoryForOriginAndType(origin, type, false,
-                                                         &error);
+  base::FilePath new_local_path = GetDirectoryForOriginAndType(origin, type,
+                                                               false, &error);
   if (error != base::PLATFORM_FILE_OK)
     return base::PLATFORM_FILE_ERROR_FAILED;
 
diff --git a/webkit/fileapi/obfuscated_file_util.h b/webkit/fileapi/obfuscated_file_util.h
index 88fc4417da8a73..f9d770bbdd306d 100644
--- a/webkit/fileapi/obfuscated_file_util.h
+++ b/webkit/fileapi/obfuscated_file_util.h
@@ -55,7 +55,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
     virtual bool HasFileSystemType(FileSystemType type) const = 0;
   };
 
-  explicit ObfuscatedFileUtil(const FilePath& file_system_directory);
+  explicit ObfuscatedFileUtil(const base::FilePath& file_system_directory);
   virtual ~ObfuscatedFileUtil();
 
   // FileSystemFileUtil overrides.
@@ -80,7 +80,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_file) OVERRIDE;
+      base::FilePath* platform_file) OVERRIDE;
   virtual scoped_ptr<AbstractFileEnumerator> CreateFileEnumerator(
       FileSystemOperationContext* context,
       const FileSystemURL& root_url,
@@ -88,7 +88,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
   virtual base::PlatformFileError GetLocalFilePath(
       FileSystemOperationContext* context,
       const FileSystemURL& file_system_url,
-      FilePath* local_path) OVERRIDE;
+      base::FilePath* local_path) OVERRIDE;
   virtual base::PlatformFileError Touch(
       FileSystemOperationContext* context,
       const FileSystemURL& url,
@@ -105,7 +105,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
       bool copy) OVERRIDE;
   virtual base::PlatformFileError CopyInForeignFile(
         FileSystemOperationContext* context,
-        const FilePath& src_file_path,
+        const base::FilePath& src_file_path,
         const FileSystemURL& dest_url) OVERRIDE;
   virtual base::PlatformFileError DeleteFile(
       FileSystemOperationContext* context,
@@ -117,7 +117,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_path,
+      base::FilePath* platform_path,
       SnapshotFilePolicy* policy) OVERRIDE;
 
   // Returns true if the directory |url| is empty.
@@ -133,7 +133,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
   // there is a file system error (e.g. the directory doesn't exist on disk and
   // |create| is false). Callers should always check |error_code| to make sure
   // the returned path is usable.
-  FilePath GetDirectoryForOriginAndType(
+  base::FilePath GetDirectoryForOriginAndType(
       const GURL& origin,
       FileSystemType type,
       bool create,
@@ -146,7 +146,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
   // TODO(ericu): This doesn't really feel like it belongs in this class.
   // The previous version lives in FileSystemPathManager, but perhaps
   // SandboxMountPointProvider would be better?
-  static FilePath::StringType GetDirectoryNameForType(FileSystemType type);
+  static base::FilePath::StringType GetDirectoryNameForType(FileSystemType type);
 
   // This method and all methods of its returned class must be called only on
   // the FILE thread.  The caller is responsible for deleting the returned
@@ -162,7 +162,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
   // this ignores all but the BaseName of the supplied path.  In order to
   // compute the cost of adding a multi-segment directory recursively, call this
   // on each path segment and add the results.
-  static int64 ComputeFilePathCost(const FilePath& path);
+  static int64 ComputeFilePathCost(const base::FilePath& path);
 
  private:
   typedef FileSystemDirectoryDatabase::FileId FileId;
@@ -178,7 +178,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
       FileId file_id,
       FileInfo* local_info,
       base::PlatformFileInfo* file_info,
-      FilePath* platform_file_path);
+      base::FilePath* platform_file_path);
 
   // Creates a new file, both the underlying backing file and the entry in the
   // database.  |dest_file_info| is an in-out parameter.  Supply the name and
@@ -193,7 +193,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
   // DCHECK and handle will hold base::kInvalidPlatformFileValue.
   base::PlatformFileError CreateFile(
       FileSystemOperationContext* context,
-      const FilePath& source_file_path,
+      const base::FilePath& source_file_path,
       const GURL& dest_origin,
       FileSystemType dest_type,
       FileInfo* dest_file_info,
@@ -203,10 +203,10 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
   // This converts from a relative path [as is stored in the FileInfo.data_path
   // field] to an absolute platform path that can be given to the native
   // filesystem.
-  FilePath DataPathToLocalPath(
+  base::FilePath DataPathToLocalPath(
       const GURL& origin,
       FileSystemType type,
-      const FilePath& data_file_path);
+      const base::FilePath& data_file_path);
 
   // This returns NULL if |create| flag is false and a filesystem does not
   // exist for the given |origin_url| and |type|.
@@ -216,7 +216,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
 
   // Gets the topmost directory specific to this origin.  This will
   // contain both the filesystem type subdirectories.
-  FilePath GetDirectoryForOrigin(const GURL& origin,
+  base::FilePath GetDirectoryForOrigin(const GURL& origin,
                                  bool create,
                                  base::PlatformFileError* error_code);
 
@@ -233,12 +233,12 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE ObfuscatedFileUtil
       FileSystemOperationContext* context,
       const GURL& origin,
       FileSystemType type,
-      FilePath* local_path);
+      base::FilePath* local_path);
 
   typedef std::map<std::string, FileSystemDirectoryDatabase*> DirectoryMap;
   DirectoryMap directories_;
   scoped_ptr<FileSystemOriginDatabase> origin_database_;
-  FilePath file_system_directory_;
+  base::FilePath file_system_directory_;
   base::OneShotTimer<ObfuscatedFileUtil> timer_;
 
   DISALLOW_COPY_AND_ASSIGN(ObfuscatedFileUtil);
diff --git a/webkit/fileapi/obfuscated_file_util_unittest.cc b/webkit/fileapi/obfuscated_file_util_unittest.cc
index f33bc6b8672035..a481c0cd9d0f81 100644
--- a/webkit/fileapi/obfuscated_file_util_unittest.cc
+++ b/webkit/fileapi/obfuscated_file_util_unittest.cc
@@ -33,11 +33,11 @@ namespace fileapi {
 
 namespace {
 
-bool FileExists(const FilePath& path) {
+bool FileExists(const base::FilePath& path) {
   return file_util::PathExists(path) && !file_util::DirectoryExists(path);
 }
 
-int64 GetSize(const FilePath& path) {
+int64 GetSize(const base::FilePath& path) {
   int64 size;
   EXPECT_TRUE(file_util::GetFileSize(path, &size));
   return size;
@@ -191,7 +191,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
     return static_cast<ObfuscatedFileUtil*>(test_helper_.file_util());
   }
 
-  const FilePath& test_directory() const {
+  const base::FilePath& test_directory() const {
     return data_dir_.path();
   }
 
@@ -234,7 +234,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
   bool PathExists(const FileSystemURL& url) {
     scoped_ptr<FileSystemOperationContext> context(NewContext(NULL));
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     base::PlatformFileError error = ofu()->GetFileInfo(
         context.get(), url, &file_info, &platform_path);
     return error == base::PLATFORM_FILE_OK;
@@ -255,7 +255,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
     return ObfuscatedFileUtil::ComputeFilePathCost(url.path());
   }
 
-  FileSystemURL CreateURL(const FilePath& path) {
+  FileSystemURL CreateURL(const base::FilePath& path) {
     return test_helper_.CreateURL(path);
   }
 
@@ -268,12 +268,12 @@ class ObfuscatedFileUtilTest : public testing::Test {
   void CheckFileAndCloseHandle(
       const FileSystemURL& url, base::PlatformFile file_handle) {
     scoped_ptr<FileSystemOperationContext> context(NewContext(NULL));
-    FilePath local_path;
+    base::FilePath local_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetLocalFilePath(
         context.get(), url, &local_path));
 
     base::PlatformFileInfo file_info0;
-    FilePath data_path;
+    base::FilePath data_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetFileInfo(
         context.get(), url, &file_info0, &data_path));
     EXPECT_EQ(data_path, local_path);
@@ -326,10 +326,10 @@ class ObfuscatedFileUtilTest : public testing::Test {
 
   void ValidateTestDirectory(
       const FileSystemURL& root_url,
-      const std::set<FilePath::StringType>& files,
-      const std::set<FilePath::StringType>& directories) {
+      const std::set<base::FilePath::StringType>& files,
+      const std::set<base::FilePath::StringType>& directories) {
     scoped_ptr<FileSystemOperationContext> context;
-    std::set<FilePath::StringType>::const_iterator iter;
+    std::set<base::FilePath::StringType>::const_iterator iter;
     for (iter = files.begin(); iter != files.end(); ++iter) {
       bool created = true;
       context.reset(NewContext(NULL));
@@ -390,8 +390,8 @@ class ObfuscatedFileUtilTest : public testing::Test {
 
   void FillTestDirectory(
       const FileSystemURL& root_url,
-      std::set<FilePath::StringType>* files,
-      std::set<FilePath::StringType>* directories) {
+      std::set<base::FilePath::StringType>* files,
+      std::set<base::FilePath::StringType>* directories) {
     scoped_ptr<FileSystemOperationContext> context;
     context.reset(NewContext(NULL));
     std::vector<base::FileUtilProxy::Entry> entries;
@@ -408,7 +408,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
     directories->insert(FILE_PATH_LITERAL("fourth"));
     directories->insert(FILE_PATH_LITERAL("fifth"));
     directories->insert(FILE_PATH_LITERAL("sixth"));
-    std::set<FilePath::StringType>::iterator iter;
+    std::set<base::FilePath::StringType>::iterator iter;
     for (iter = files->begin(); iter != files->end(); ++iter) {
       bool created = false;
       context.reset(NewContext(NULL));
@@ -432,8 +432,8 @@ class ObfuscatedFileUtilTest : public testing::Test {
   }
 
   void TestReadDirectoryHelper(const FileSystemURL& root_url) {
-    std::set<FilePath::StringType> files;
-    std::set<FilePath::StringType> directories;
+    std::set<base::FilePath::StringType> files;
+    std::set<base::FilePath::StringType> directories;
     FillTestDirectory(root_url, &files, &directories);
 
     scoped_ptr<FileSystemOperationContext> context;
@@ -448,7 +448,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
     for (entry_iter = entries.begin(); entry_iter != entries.end();
         ++entry_iter) {
       const base::FileUtilProxy::Entry& entry = *entry_iter;
-      std::set<FilePath::StringType>::iterator iter = files.find(entry.name);
+      std::set<base::FilePath::StringType>::iterator iter = files.find(entry.name);
       if (iter != files.end()) {
         EXPECT_FALSE(entry.is_directory);
         files.erase(iter);
@@ -471,7 +471,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
                   context.get(), url, last_access_time, last_modified_time));
     // Currently we fire no change notifications for Touch.
     EXPECT_TRUE(change_observer()->HasNoChange());
-    FilePath local_path;
+    base::FilePath local_path;
     base::PlatformFileInfo file_info;
     context.reset(NewContext(NULL));
     EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetFileInfo(
@@ -499,8 +499,8 @@ class ObfuscatedFileUtilTest : public testing::Test {
   void TestCopyInForeignFileHelper(bool overwrite) {
     base::ScopedTempDir source_dir;
     ASSERT_TRUE(source_dir.CreateUniqueTempDir());
-    FilePath root_file_path = source_dir.path();
-    FilePath src_file_path = root_file_path.AppendASCII("file_name");
+    base::FilePath root_file_path = source_dir.path();
+    base::FilePath src_file_path = root_file_path.AppendASCII("file_name");
     FileSystemURL dest_url = CreateURLFromUTF8("new file");
     int64 src_file_length = 87;
 
@@ -551,7 +551,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
 
     context.reset(NewContext(NULL));
     base::PlatformFileInfo file_info;
-    FilePath data_path;
+    base::FilePath data_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetFileInfo(
         context.get(), dest_url, &file_info, &data_path));
     EXPECT_NE(data_path, src_file_path);
@@ -571,7 +571,7 @@ class ObfuscatedFileUtilTest : public testing::Test {
 
   base::Time GetModifiedTime(const FileSystemURL& url) {
     scoped_ptr<FileSystemOperationContext> context(NewContext(NULL));
-    FilePath data_path;
+    base::FilePath data_path;
     base::PlatformFileInfo file_info;
     context.reset(NewContext(NULL));
     EXPECT_EQ(base::PLATFORM_FILE_OK,
@@ -693,7 +693,7 @@ TEST_F(ObfuscatedFileUtilTest, TestCreateAndDeleteFile) {
   CheckFileAndCloseHandle(url, file_handle);
 
   context.reset(NewContext(NULL));
-  FilePath local_path;
+  base::FilePath local_path;
   EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetLocalFilePath(
       context.get(), url, &local_path));
   EXPECT_TRUE(file_util::PathExists(local_path));
@@ -761,7 +761,7 @@ TEST_F(ObfuscatedFileUtilTest, TestTruncate) {
   EXPECT_EQ(1, change_observer()->get_and_reset_create_file_count());
 
   context.reset(NewContext(NULL));
-  FilePath local_path;
+  base::FilePath local_path;
   EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetLocalFilePath(
       context.get(), url, &local_path));
   EXPECT_EQ(0, GetSize(local_path));
@@ -837,7 +837,7 @@ TEST_F(ObfuscatedFileUtilTest, TestQuotaOnTruncation) {
   }
 
   // Delete backing file to make following truncation fail.
-  FilePath local_path;
+  base::FilePath local_path;
   ASSERT_EQ(base::PLATFORM_FILE_OK,
             ofu()->GetLocalFilePath(
                 UnlimitedContext().get(),
@@ -954,7 +954,7 @@ TEST_F(ObfuscatedFileUtilTest, TestDirectoryOps) {
   EXPECT_TRUE(change_observer()->HasNoChange());
 
   base::PlatformFileInfo file_info;
-  FilePath local_path;
+  base::FilePath local_path;
   EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetFileInfo(
       context.get(), url, &file_info, &local_path));
   EXPECT_TRUE(local_path.empty());
@@ -1138,13 +1138,13 @@ TEST_F(ObfuscatedFileUtilTest, TestPathQuotas) {
   bool exclusive = true;
   bool recursive = true;
   url = CreateURLFromUTF8("directory/to/use");
-  std::vector<FilePath::StringType> components;
+  std::vector<base::FilePath::StringType> components;
   url.path().GetComponents(&components);
   path_cost = 0;
-  for (std::vector<FilePath::StringType>::iterator iter = components.begin();
+  for (std::vector<base::FilePath::StringType>::iterator iter = components.begin();
       iter != components.end(); ++iter) {
     path_cost += ObfuscatedFileUtil::ComputeFilePathCost(
-        FilePath(*iter));
+        base::FilePath(*iter));
   }
   context.reset(NewContext(NULL));
   context->set_allowed_bytes_growth(1024);
@@ -1250,7 +1250,7 @@ TEST_F(ObfuscatedFileUtilTest, TestCopyOrMoveFileSuccess) {
 
     if (test_case.is_copy_not_move) {
       base::PlatformFileInfo file_info;
-      FilePath local_path;
+      base::FilePath local_path;
       context.reset(NewContext(NULL));
       EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetFileInfo(
           context.get(), source_url, &file_info, &local_path));
@@ -1259,13 +1259,13 @@ TEST_F(ObfuscatedFileUtilTest, TestCopyOrMoveFileSuccess) {
                 ofu()->DeleteFile(context.get(), source_url));
     } else {
       base::PlatformFileInfo file_info;
-      FilePath local_path;
+      base::FilePath local_path;
       context.reset(NewContext(NULL));
       EXPECT_EQ(base::PLATFORM_FILE_ERROR_NOT_FOUND, ofu()->GetFileInfo(
           context.get(), source_url, &file_info, &local_path));
     }
     base::PlatformFileInfo file_info;
-    FilePath local_path;
+    base::FilePath local_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK, ofu()->GetFileInfo(
         context.get(), dest_url, &file_info, &local_path));
     EXPECT_EQ(kSourceLength, file_info.size);
@@ -1389,8 +1389,8 @@ TEST_F(ObfuscatedFileUtilTest, TestEnumerator) {
   ASSERT_EQ(base::PLATFORM_FILE_OK, ofu()->CreateDirectory(
       context.get(), src_url, exclusive, recursive));
 
-  std::set<FilePath::StringType> files;
-  std::set<FilePath::StringType> directories;
+  std::set<base::FilePath::StringType> files;
+  std::set<base::FilePath::StringType> directories;
   FillTestDirectory(src_url, &files, &directories);
 
   FileSystemURL dest_url = CreateURLFromUTF8("destination dir");
@@ -1505,7 +1505,7 @@ TEST_F(ObfuscatedFileUtilTest, TestRevokeUsageCache) {
   for (size_t i = 0; i < test::kRegularTestCaseSize; ++i) {
     SCOPED_TRACE(testing::Message() << "Creating kRegularTestCase " << i);
     const test::TestCaseRecord& test_case = test::kRegularTestCases[i];
-    FilePath file_path(test_case.path);
+    base::FilePath file_path(test_case.path);
     expected_quota += ObfuscatedFileUtil::ComputeFilePathCost(file_path);
     if (test_case.is_directory) {
       bool exclusive = true;
@@ -1550,7 +1550,7 @@ TEST_F(ObfuscatedFileUtilTest, TestInconsistency) {
   scoped_ptr<FileSystemOperationContext> context;
   base::PlatformFile file;
   base::PlatformFileInfo file_info;
-  FilePath data_path;
+  base::FilePath data_path;
   bool created = false;
 
   // Create a non-empty file.
@@ -1625,7 +1625,7 @@ TEST_F(ObfuscatedFileUtilTest, TestIncompleteDirectoryReading) {
     CreateURLFromUTF8("bar"),
     CreateURLFromUTF8("baz")
   };
-  const FileSystemURL empty_path = CreateURL(FilePath());
+  const FileSystemURL empty_path = CreateURL(base::FilePath());
   scoped_ptr<FileSystemOperationContext> context;
 
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kPath); ++i) {
@@ -1644,7 +1644,7 @@ TEST_F(ObfuscatedFileUtilTest, TestIncompleteDirectoryReading) {
   EXPECT_EQ(3u, entries.size());
 
   context.reset(NewContext(NULL));
-  FilePath local_path;
+  base::FilePath local_path;
   EXPECT_EQ(base::PLATFORM_FILE_OK,
             ofu()->GetLocalFilePath(context.get(), kPath[0], &local_path));
   EXPECT_TRUE(file_util::Delete(local_path, false));
@@ -1780,7 +1780,7 @@ TEST_F(ObfuscatedFileUtilTest, TestDirectoryTimestampForCreation) {
   EXPECT_EQ(base::PLATFORM_FILE_OK,
             ofu()->EnsureFileExists(context.get(), src_path, &created));
   EXPECT_TRUE(created);
-  FilePath src_local_path;
+  base::FilePath src_local_path;
   context.reset(NewContext(NULL));
   EXPECT_EQ(base::PLATFORM_FILE_OK,
             ofu()->GetLocalFilePath(context.get(), src_path, &src_local_path));
@@ -1883,7 +1883,7 @@ TEST_F(ObfuscatedFileUtilTest, TestFileEnumeratorTimestamp) {
   EXPECT_EQ(base::PLATFORM_FILE_OK,
             ofu()->CreateDirectory(context.get(), url2, false, false));
 
-  FilePath file_path;
+  base::FilePath file_path;
   context.reset(NewContext(NULL));
   EXPECT_EQ(base::PLATFORM_FILE_OK,
             ofu()->GetLocalFilePath(context.get(), url1, &file_path));
@@ -1900,11 +1900,11 @@ TEST_F(ObfuscatedFileUtilTest, TestFileEnumeratorTimestamp) {
       ofu()->CreateFileEnumerator(context.get(), dir, false));
 
   int count = 0;
-  FilePath file_path_each;
+  base::FilePath file_path_each;
   while (!(file_path_each = file_enum->Next()).empty()) {
     context.reset(NewContext(NULL));
     base::PlatformFileInfo file_info;
-    FilePath file_path;
+    base::FilePath file_path;
     EXPECT_EQ(base::PLATFORM_FILE_OK,
               ofu()->GetFileInfo(context.get(),
                                  dir.WithPath(file_path_each),
diff --git a/webkit/fileapi/remote_file_system_proxy.h b/webkit/fileapi/remote_file_system_proxy.h
index e54a266372b48d..2d3ba77fa915c4 100644
--- a/webkit/fileapi/remote_file_system_proxy.h
+++ b/webkit/fileapi/remote_file_system_proxy.h
@@ -13,7 +13,7 @@ namespace fileapi {
 
 typedef base::Callback<
     void(base::PlatformFileError result,
-         const FilePath& platform_path,
+         const base::FilePath& platform_path,
          const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref)>
     WritableSnapshotFile;
 
diff --git a/webkit/fileapi/sandbox_file_stream_writer.cc b/webkit/fileapi/sandbox_file_stream_writer.cc
index 036c4dd35cc7cd..7906f174451be0 100644
--- a/webkit/fileapi/sandbox_file_stream_writer.cc
+++ b/webkit/fileapi/sandbox_file_stream_writer.cc
@@ -121,7 +121,7 @@ void SandboxFileStreamWriter::DidGetFileInfo(
     const net::CompletionCallback& callback,
     base::PlatformFileError file_error,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   if (CancelIfRequested())
     return;
   if (file_error != base::PLATFORM_FILE_OK) {
diff --git a/webkit/fileapi/sandbox_file_stream_writer.h b/webkit/fileapi/sandbox_file_stream_writer.h
index a1f0e199196924..c1dfe18370f4a6 100644
--- a/webkit/fileapi/sandbox_file_stream_writer.h
+++ b/webkit/fileapi/sandbox_file_stream_writer.h
@@ -52,7 +52,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE SandboxFileStreamWriter
   void DidGetFileInfo(const net::CompletionCallback& callback,
                       base::PlatformFileError file_error,
                       const base::PlatformFileInfo& file_info,
-                      const FilePath& platform_path);
+                      const base::FilePath& platform_path);
   void DidGetUsageAndQuota(const net::CompletionCallback& callback,
                            quota::QuotaStatusCode status,
                            int64 usage, int64 quota);
@@ -74,7 +74,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE SandboxFileStreamWriter
 
   UpdateObserverList observers_;
 
-  FilePath file_path_;
+  base::FilePath file_path_;
   int64 file_size_;
   int64 total_bytes_written_;
   int64 allowed_bytes_to_write_;
diff --git a/webkit/fileapi/sandbox_mount_point_provider.cc b/webkit/fileapi/sandbox_mount_point_provider.cc
index baf7cac7fd76f2..a7121ac0a0d409 100644
--- a/webkit/fileapi/sandbox_mount_point_provider.cc
+++ b/webkit/fileapi/sandbox_mount_point_provider.cc
@@ -63,12 +63,12 @@ const char kPersistentOriginsCountLabel[] = "FileSystem.PersistentOriginsCount";
 
 // Restricted names.
 // http://dev.w3.org/2009/dap/file-system/file-dir-sys.html#naming-restrictions
-const FilePath::CharType* const kRestrictedNames[] = {
+const base::FilePath::CharType* const kRestrictedNames[] = {
   FILE_PATH_LITERAL("."), FILE_PATH_LITERAL(".."),
 };
 
 // Restricted chars.
-const FilePath::CharType kRestrictedChars[] = {
+const base::FilePath::CharType kRestrictedChars[] = {
   FILE_PATH_LITERAL('/'), FILE_PATH_LITERAL('\\'),
 };
 
@@ -109,7 +109,7 @@ void ValidateRootOnFileThread(
     base::PlatformFileError* error_ptr) {
   DCHECK(error_ptr);
 
-  FilePath root_path =
+  base::FilePath root_path =
       file_util->GetDirectoryForOriginAndType(
           origin_url, type, create, error_ptr);
   if (*error_ptr != base::PLATFORM_FILE_OK) {
@@ -126,7 +126,7 @@ void ValidateRootOnFileThread(
 
 }  // anonymous namespace
 
-const FilePath::CharType SandboxMountPointProvider::kFileSystemDirectory[] =
+const base::FilePath::CharType SandboxMountPointProvider::kFileSystemDirectory[] =
     FILE_PATH_LITERAL("File System");
 
 // static
@@ -139,7 +139,7 @@ bool SandboxMountPointProvider::CanHandleType(FileSystemType type) {
 SandboxMountPointProvider::SandboxMountPointProvider(
     quota::QuotaManagerProxy* quota_manager_proxy,
     base::SequencedTaskRunner* file_task_runner,
-    const FilePath& profile_path,
+    const base::FilePath& profile_path,
     const FileSystemOptions& file_system_options)
     : file_task_runner_(file_task_runner),
       profile_path_(profile_path),
@@ -211,16 +211,16 @@ void SandboxMountPointProvider::ValidateFileSystemRoot(
                  callback, base::Owned(error_ptr)));
 };
 
-FilePath
+base::FilePath
 SandboxMountPointProvider::GetFileSystemRootPathOnFileThread(
     const FileSystemURL& url,
     bool create) {
   if (file_system_options_.is_incognito())
     // TODO(kinuko): return an isolated temporary directory.
-    return FilePath();
+    return base::FilePath();
 
   if (!IsAllowedScheme(url.origin()))
-    return FilePath();
+    return base::FilePath();
 
   return GetBaseDirectoryForOriginAndType(url.origin(), url.type(), create);
 }
@@ -233,7 +233,7 @@ bool SandboxMountPointProvider::IsAccessAllowed(const FileSystemURL& url) {
   return IsAllowedScheme(url.origin());
 }
 
-bool SandboxMountPointProvider::IsRestrictedFileName(const FilePath& filename)
+bool SandboxMountPointProvider::IsRestrictedFileName(const base::FilePath& filename)
     const {
   if (filename.value().empty())
     return false;
@@ -246,7 +246,7 @@ bool SandboxMountPointProvider::IsRestrictedFileName(const FilePath& filename)
 
   for (size_t i = 0; i < arraysize(kRestrictedChars); ++i) {
     if (filename.value().find(kRestrictedChars[i]) !=
-        FilePath::StringType::npos)
+        base::FilePath::StringType::npos)
       return true;
   }
 
@@ -341,14 +341,14 @@ SandboxMountPointProvider::CreateOriginEnumerator() {
   return new ObfuscatedOriginEnumerator(sandbox_sync_file_util());
 }
 
-FilePath SandboxMountPointProvider::GetBaseDirectoryForOriginAndType(
+base::FilePath SandboxMountPointProvider::GetBaseDirectoryForOriginAndType(
     const GURL& origin_url, fileapi::FileSystemType type, bool create) {
 
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath path = sandbox_sync_file_util()->GetDirectoryForOriginAndType(
+  base::FilePath path = sandbox_sync_file_util()->GetDirectoryForOriginAndType(
       origin_url, type, create, &error);
   if (error != base::PLATFORM_FILE_OK)
-    return FilePath();
+    return base::FilePath();
   return path;
 }
 
@@ -418,10 +418,10 @@ int64 SandboxMountPointProvider::GetOriginUsageOnFileThread(
     const GURL& origin_url,
     fileapi::FileSystemType type) {
   DCHECK(CanHandleType(type));
-  FilePath base_path =
+  base::FilePath base_path =
       GetBaseDirectoryForOriginAndType(origin_url, type, false);
   if (base_path.empty() || !file_util::DirectoryExists(base_path)) return 0;
-  FilePath usage_file_path =
+  base::FilePath usage_file_path =
       base_path.Append(FileSystemUsageCache::kUsageFileName);
 
   bool is_valid = FileSystemUsageCache::IsValid(usage_file_path);
@@ -439,11 +439,11 @@ int64 SandboxMountPointProvider::GetOriginUsageOnFileThread(
 
   FileSystemOperationContext context(file_system_context);
   FileSystemURL url = file_system_context->CreateCrackedFileSystemURL(
-      origin_url, type, FilePath());
+      origin_url, type, base::FilePath());
   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> enumerator(
       sandbox_sync_file_util()->CreateFileEnumerator(&context, url, true));
 
-  FilePath file_path_each;
+  base::FilePath file_path_each;
   int64 usage = 0;
 
   while (!(file_path_each = enumerator->Next()).empty()) {
@@ -459,7 +459,7 @@ void SandboxMountPointProvider::InvalidateUsageCache(
     const GURL& origin_url, fileapi::FileSystemType type) {
   DCHECK(CanHandleType(type));
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath usage_file_path = GetUsageCachePathForOriginAndType(
+  base::FilePath usage_file_path = GetUsageCachePathForOriginAndType(
       sandbox_sync_file_util(), origin_url, type, &error);
   if (error != base::PLATFORM_FILE_OK)
     return;
@@ -540,29 +540,29 @@ SandboxMountPointProvider::CreateFileSystemOperationForSync(
                                       operation_context.Pass());
 }
 
-FilePath SandboxMountPointProvider::GetUsageCachePathForOriginAndType(
+base::FilePath SandboxMountPointProvider::GetUsageCachePathForOriginAndType(
     const GURL& origin_url,
     FileSystemType type) {
   base::PlatformFileError error;
-  FilePath path = GetUsageCachePathForOriginAndType(
+  base::FilePath path = GetUsageCachePathForOriginAndType(
       sandbox_sync_file_util(), origin_url, type, &error);
   if (error != base::PLATFORM_FILE_OK)
-    return FilePath();
+    return base::FilePath();
   return path;
 }
 
 // static
-FilePath SandboxMountPointProvider::GetUsageCachePathForOriginAndType(
+base::FilePath SandboxMountPointProvider::GetUsageCachePathForOriginAndType(
     ObfuscatedFileUtil* sandbox_file_util,
     const GURL& origin_url,
     fileapi::FileSystemType type,
     base::PlatformFileError* error_out) {
   DCHECK(error_out);
   *error_out = base::PLATFORM_FILE_OK;
-  FilePath base_path = sandbox_file_util->GetDirectoryForOriginAndType(
+  base::FilePath base_path = sandbox_file_util->GetDirectoryForOriginAndType(
       origin_url, type, false /* create */, error_out);
   if (*error_out != base::PLATFORM_FILE_OK)
-    return FilePath();
+    return base::FilePath();
   return base_path.Append(FileSystemUsageCache::kUsageFileName);
 }
 
diff --git a/webkit/fileapi/sandbox_mount_point_provider.h b/webkit/fileapi/sandbox_mount_point_provider.h
index 2a8a3ff6260216..61768758451385 100644
--- a/webkit/fileapi/sandbox_mount_point_provider.h
+++ b/webkit/fileapi/sandbox_mount_point_provider.h
@@ -59,7 +59,7 @@ class WEBKIT_STORAGE_EXPORT SandboxMountPointProvider
   };
 
   // The FileSystem directory name.
-  static const FilePath::CharType kFileSystemDirectory[];
+  static const base::FilePath::CharType kFileSystemDirectory[];
 
   static bool CanHandleType(FileSystemType type);
 
@@ -68,7 +68,7 @@ class WEBKIT_STORAGE_EXPORT SandboxMountPointProvider
   SandboxMountPointProvider(
       quota::QuotaManagerProxy* quota_manager_proxy,
       base::SequencedTaskRunner* file_task_runner,
-      const FilePath& profile_path,
+      const base::FilePath& profile_path,
       const FileSystemOptions& file_system_options);
   virtual ~SandboxMountPointProvider();
 
@@ -78,11 +78,11 @@ class WEBKIT_STORAGE_EXPORT SandboxMountPointProvider
       FileSystemType type,
       bool create,
       const ValidateFileSystemCallback& callback) OVERRIDE;
-  virtual FilePath GetFileSystemRootPathOnFileThread(
+  virtual base::FilePath GetFileSystemRootPathOnFileThread(
       const FileSystemURL& url,
       bool create) OVERRIDE;
   virtual bool IsAccessAllowed(const FileSystemURL& url) OVERRIDE;
-  virtual bool IsRestrictedFileName(const FilePath& filename) const OVERRIDE;
+  virtual bool IsRestrictedFileName(const base::FilePath& filename) const OVERRIDE;
   virtual FileSystemFileUtil* GetFileUtil(FileSystemType type) OVERRIDE;
   virtual AsyncFileUtil* GetAsyncFileUtil(FileSystemType type) OVERRIDE;
   virtual FilePermissionPolicy GetPermissionPolicy(
@@ -118,7 +118,7 @@ class WEBKIT_STORAGE_EXPORT SandboxMountPointProvider
   // the 'unique' part.)
   // Returns an empty path if the given type is invalid.
   // This method can only be called on the file thread.
-  FilePath GetBaseDirectoryForOriginAndType(
+  base::FilePath GetBaseDirectoryForOriginAndType(
       const GURL& origin_url,
       FileSystemType type,
       bool create);
@@ -174,12 +174,12 @@ class WEBKIT_STORAGE_EXPORT SandboxMountPointProvider
   friend class SyncableFileSystemOperation;
 
   // Returns a path to the usage cache file.
-  FilePath GetUsageCachePathForOriginAndType(
+  base::FilePath GetUsageCachePathForOriginAndType(
       const GURL& origin_url,
       FileSystemType type);
 
   // Returns a path to the usage cache file (static version).
-  static FilePath GetUsageCachePathForOriginAndType(
+  static base::FilePath GetUsageCachePathForOriginAndType(
       ObfuscatedFileUtil* sandbox_file_util,
       const GURL& origin_url,
       FileSystemType type,
@@ -202,7 +202,7 @@ class WEBKIT_STORAGE_EXPORT SandboxMountPointProvider
 
   scoped_refptr<base::SequencedTaskRunner> file_task_runner_;
 
-  const FilePath profile_path_;
+  const base::FilePath profile_path_;
 
   FileSystemOptions file_system_options_;
 
diff --git a/webkit/fileapi/sandbox_mount_point_provider_unittest.cc b/webkit/fileapi/sandbox_mount_point_provider_unittest.cc
index 875ab769685879..9d5111419b7b4e 100644
--- a/webkit/fileapi/sandbox_mount_point_provider_unittest.cc
+++ b/webkit/fileapi/sandbox_mount_point_provider_unittest.cc
@@ -39,7 +39,7 @@ class SandboxMountPointProviderOriginEnumeratorTest : public testing::Test {
  protected:
   void CreateOriginTypeDirectory(const GURL& origin,
                                  fileapi::FileSystemType type) {
-    FilePath target = sandbox_provider_->
+    base::FilePath target = sandbox_provider_->
         GetBaseDirectoryForOriginAndType(origin, type, true);
     ASSERT_TRUE(!target.empty());
     ASSERT_TRUE(file_util::DirectoryExists(target));
diff --git a/webkit/fileapi/sandbox_quota_observer.cc b/webkit/fileapi/sandbox_quota_observer.cc
index ec24d37a3a568f..c12ddb29e9b02f 100644
--- a/webkit/fileapi/sandbox_quota_observer.cc
+++ b/webkit/fileapi/sandbox_quota_observer.cc
@@ -29,7 +29,7 @@ SandboxQuotaObserver::~SandboxQuotaObserver() {}
 void SandboxQuotaObserver::OnStartUpdate(const FileSystemURL& url) {
   DCHECK(SandboxMountPointProvider::CanHandleType(url.type()));
   DCHECK(update_notify_runner_->RunsTasksOnCurrentThread());
-  FilePath usage_file_path = GetUsageCachePath(url);
+  base::FilePath usage_file_path = GetUsageCachePath(url);
   if (usage_file_path.empty())
     return;
   FileSystemUsageCache::IncrementDirty(usage_file_path);
@@ -48,7 +48,7 @@ void SandboxQuotaObserver::OnUpdate(const FileSystemURL& url,
         delta);
   }
 
-  FilePath usage_file_path = GetUsageCachePath(url);
+  base::FilePath usage_file_path = GetUsageCachePath(url);
   if (usage_file_path.empty())
     return;
 
@@ -65,7 +65,7 @@ void SandboxQuotaObserver::OnEndUpdate(const FileSystemURL& url) {
   DCHECK(SandboxMountPointProvider::CanHandleType(url.type()));
   DCHECK(update_notify_runner_->RunsTasksOnCurrentThread());
 
-  FilePath usage_file_path = GetUsageCachePath(url);
+  base::FilePath usage_file_path = GetUsageCachePath(url);
   if (usage_file_path.empty())
     return;
 
@@ -89,15 +89,15 @@ void SandboxQuotaObserver::OnAccess(const FileSystemURL& url) {
   }
 }
 
-FilePath SandboxQuotaObserver::GetUsageCachePath(const FileSystemURL& url) {
+base::FilePath SandboxQuotaObserver::GetUsageCachePath(const FileSystemURL& url) {
   DCHECK(sandbox_file_util_);
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
-  FilePath path = SandboxMountPointProvider::GetUsageCachePathForOriginAndType(
+  base::FilePath path = SandboxMountPointProvider::GetUsageCachePathForOriginAndType(
       sandbox_file_util_, url.origin(), url.type(), &error);
   if (error != base::PLATFORM_FILE_OK) {
     LOG(WARNING) << "Could not get usage cache path for: "
                  << url.DebugString();
-    return FilePath();
+    return base::FilePath();
   }
   return path;
 }
@@ -114,7 +114,7 @@ void SandboxQuotaObserver::ApplyPendingUsageUpdate() {
 }
 
 void SandboxQuotaObserver::UpdateUsageCacheFile(
-    const FilePath& usage_file_path,
+    const base::FilePath& usage_file_path,
     int64 delta) {
   DCHECK(!usage_file_path.empty());
   if (!usage_file_path.empty() && delta != 0)
diff --git a/webkit/fileapi/sandbox_quota_observer.h b/webkit/fileapi/sandbox_quota_observer.h
index 4711ec007e1bb4..ea971a4179a61d 100644
--- a/webkit/fileapi/sandbox_quota_observer.h
+++ b/webkit/fileapi/sandbox_quota_observer.h
@@ -33,7 +33,7 @@ class SandboxQuotaObserver
     : public FileUpdateObserver,
       public FileAccessObserver {
  public:
-  typedef std::map<FilePath, int64> PendingUpdateNotificationMap;
+  typedef std::map<base::FilePath, int64> PendingUpdateNotificationMap;
 
   SandboxQuotaObserver(
       quota::QuotaManagerProxy* quota_manager_proxy,
@@ -51,9 +51,9 @@ class SandboxQuotaObserver
 
  private:
   void ApplyPendingUsageUpdate();
-  void UpdateUsageCacheFile(const FilePath& usage_file_path, int64 delta);
+  void UpdateUsageCacheFile(const base::FilePath& usage_file_path, int64 delta);
 
-  FilePath GetUsageCachePath(const FileSystemURL& url);
+  base::FilePath GetUsageCachePath(const FileSystemURL& url);
 
   scoped_refptr<quota::QuotaManagerProxy> quota_manager_proxy_;
   scoped_refptr<base::SequencedTaskRunner> update_notify_runner_;
diff --git a/webkit/fileapi/syncable/canned_syncable_file_system.cc b/webkit/fileapi/syncable/canned_syncable_file_system.cc
index e2746e548b7113..d6c7c4db063050 100644
--- a/webkit/fileapi/syncable/canned_syncable_file_system.cc
+++ b/webkit/fileapi/syncable/canned_syncable_file_system.cc
@@ -89,7 +89,7 @@ void OnGetMetadataAndVerifyData(
     const CannedSyncableFileSystem::StatusCallback& callback,
     base::PlatformFileError result,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   if (result != base::PLATFORM_FILE_OK) {
     callback.Run(result);
     return;
@@ -104,11 +104,11 @@ void OnGetMetadataAndVerifyData(
 
 void OnGetMetadata(
     base::PlatformFileInfo* file_info_out,
-    FilePath* platform_path_out,
+    base::FilePath* platform_path_out,
     const CannedSyncableFileSystem::StatusCallback& callback,
     base::PlatformFileError result,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   DCHECK(file_info_out);
   DCHECK(platform_path_out);
   *file_info_out = file_info;
@@ -375,7 +375,7 @@ PlatformFileError CannedSyncableFileSystem::VerifyFile(
 PlatformFileError CannedSyncableFileSystem::GetMetadata(
     const FileSystemURL& url,
     base::PlatformFileInfo* info,
-    FilePath* platform_path) {
+    base::FilePath* platform_path) {
   return RunOnThread<PlatformFileError>(
       io_task_runner_,
       FROM_HERE,
@@ -540,7 +540,7 @@ void CannedSyncableFileSystem::DoVerifyFile(
 void CannedSyncableFileSystem::DoGetMetadata(
     const FileSystemURL& url,
     base::PlatformFileInfo* info,
-    FilePath* platform_path,
+    base::FilePath* platform_path,
     const StatusCallback& callback) {
   EXPECT_TRUE(is_filesystem_opened_);
   NewOperation()->GetMetadata(
diff --git a/webkit/fileapi/syncable/canned_syncable_file_system.h b/webkit/fileapi/syncable/canned_syncable_file_system.h
index f2970682372e27..d520387a7a1d00 100644
--- a/webkit/fileapi/syncable/canned_syncable_file_system.h
+++ b/webkit/fileapi/syncable/canned_syncable_file_system.h
@@ -110,7 +110,7 @@ class CannedSyncableFileSystem
                                      const std::string& expected_data);
   base::PlatformFileError GetMetadata(const FileSystemURL& url,
                                       base::PlatformFileInfo* info,
-                                      FilePath* platform_path);
+                                      base::FilePath* platform_path);
 
   // Returns the # of bytes written (>=0) or an error code (<0).
   int64 Write(net::URLRequestContext* url_request_context,
@@ -172,7 +172,7 @@ class CannedSyncableFileSystem
                     const StatusCallback& callback);
   void DoGetMetadata(const FileSystemURL& url,
                      base::PlatformFileInfo* info,
-                     FilePath* platform_path,
+                     base::FilePath* platform_path,
                      const StatusCallback& callback);
   void DoWrite(net::URLRequestContext* url_request_context,
                const FileSystemURL& url,
diff --git a/webkit/fileapi/syncable/local_file_change_tracker.cc b/webkit/fileapi/syncable/local_file_change_tracker.cc
index b5ee20d20020d1..42573509d023f6 100644
--- a/webkit/fileapi/syncable/local_file_change_tracker.cc
+++ b/webkit/fileapi/syncable/local_file_change_tracker.cc
@@ -21,7 +21,7 @@
 namespace fileapi {
 
 namespace {
-const FilePath::CharType kDatabaseName[] =
+const base::FilePath::CharType kDatabaseName[] =
     FILE_PATH_LITERAL("LocalFileChangeTracker");
 const char kMark[] = "d";
 }  // namespace
@@ -30,7 +30,7 @@ const char kMark[] = "d";
 // object must be destructed on file_task_runner.
 class LocalFileChangeTracker::TrackerDB {
  public:
-  explicit TrackerDB(const FilePath& base_path);
+  explicit TrackerDB(const base::FilePath& base_path);
 
   SyncStatusCode MarkDirty(const std::string& url);
   SyncStatusCode ClearDirty(const std::string& url);
@@ -47,7 +47,7 @@ class LocalFileChangeTracker::TrackerDB {
   void HandleError(const tracked_objects::Location& from_here,
                    const leveldb::Status& status);
 
-  const FilePath base_path_;
+  const base::FilePath base_path_;
   scoped_ptr<leveldb::DB> db_;
   SyncStatusCode db_status_;
 
@@ -60,7 +60,7 @@ LocalFileChangeTracker::ChangeInfo::~ChangeInfo() {}
 // LocalFileChangeTracker ------------------------------------------------------
 
 LocalFileChangeTracker::LocalFileChangeTracker(
-    const FilePath& base_path,
+    const base::FilePath& base_path,
     base::SequencedTaskRunner* file_task_runner)
     : initialized_(false),
       file_task_runner_(file_task_runner),
@@ -217,7 +217,7 @@ SyncStatusCode LocalFileChangeTracker::CollectLastDirtyChanges(
       new FileSystemOperationContext(file_system_context));
 
   base::PlatformFileInfo file_info;
-  FilePath platform_path;
+  base::FilePath platform_path;
 
   while (!dirty_files.empty()) {
     const FileSystemURL url = dirty_files.front();
@@ -241,7 +241,7 @@ SyncStatusCode LocalFileChangeTracker::CollectLastDirtyChanges(
             file_util->CreateFileEnumerator(context.get(),
                                             url,
                                             false /* recursive */));
-        FilePath path_each;
+        base::FilePath path_each;
         while (!(path_each = enumerator->Next()).empty()) {
           dirty_files.push(CreateSyncableFileSystemURL(
               url.origin(), url.filesystem_id(), path_each));
@@ -288,7 +288,7 @@ void LocalFileChangeTracker::RecordChange(
 
 // TrackerDB -------------------------------------------------------------------
 
-LocalFileChangeTracker::TrackerDB::TrackerDB(const FilePath& base_path)
+LocalFileChangeTracker::TrackerDB::TrackerDB(const base::FilePath& base_path)
   : base_path_(base_path),
     db_status_(SYNC_STATUS_OK) {}
 
diff --git a/webkit/fileapi/syncable/local_file_change_tracker.h b/webkit/fileapi/syncable/local_file_change_tracker.h
index 963602717d3bc1..b92ddaa44eb64e 100644
--- a/webkit/fileapi/syncable/local_file_change_tracker.h
+++ b/webkit/fileapi/syncable/local_file_change_tracker.h
@@ -39,7 +39,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileChangeTracker
   // |file_task_runner| must be the one where the observee file operations run.
   // (So that we can make sure DB operations are done before actual update
   // happens)
-  LocalFileChangeTracker(const FilePath& base_path,
+  LocalFileChangeTracker(const base::FilePath& base_path,
                          base::SequencedTaskRunner* file_task_runner);
   virtual ~LocalFileChangeTracker();
 
diff --git a/webkit/fileapi/syncable/local_file_sync_context.cc b/webkit/fileapi/syncable/local_file_sync_context.cc
index 367e848d137ab7..b237aaafb83d14 100644
--- a/webkit/fileapi/syncable/local_file_sync_context.cc
+++ b/webkit/fileapi/syncable/local_file_sync_context.cc
@@ -174,7 +174,7 @@ void LocalFileSyncContext::RegisterURLForWaitingSync(
 void LocalFileSyncContext::ApplyRemoteChange(
     FileSystemContext* file_system_context,
     const FileChange& change,
-    const FilePath& local_path,
+    const base::FilePath& local_path,
     const FileSystemURL& url,
     const SyncStatusCallback& callback) {
   if (!io_task_runner_->RunsTasksOnCurrentThread()) {
@@ -564,7 +564,7 @@ void LocalFileSyncContext::DidGetWritingStatusForSync(
   FileChangeList changes;
   file_system_context->change_tracker()->GetChangesForURL(url, &changes);
 
-  FilePath platform_path;
+  base::FilePath platform_path;
   base::PlatformFileInfo file_info;
   FileSystemFileUtil* file_util = file_system_context->GetFileUtil(url.type());
   DCHECK(file_util);
@@ -624,7 +624,7 @@ void LocalFileSyncContext::DidGetFileMetadata(
     const SyncFileMetadataCallback& callback,
     base::PlatformFileError file_error,
     const base::PlatformFileInfo& file_info,
-    const FilePath& platform_path) {
+    const base::FilePath& platform_path) {
   DCHECK(io_task_runner_->RunsTasksOnCurrentThread());
   SyncFileMetadata metadata;
   if (file_error == base::PLATFORM_FILE_OK) {
diff --git a/webkit/fileapi/syncable/local_file_sync_context.h b/webkit/fileapi/syncable/local_file_sync_context.h
index 6ffc901ca1dda3..a2107f2a4c1ea6 100644
--- a/webkit/fileapi/syncable/local_file_sync_context.h
+++ b/webkit/fileapi/syncable/local_file_sync_context.h
@@ -115,7 +115,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSyncContext
   void ApplyRemoteChange(
       FileSystemContext* file_system_context,
       const FileChange& change,
-      const FilePath& local_path,
+      const base::FilePath& local_path,
       const FileSystemURL& url,
       const SyncStatusCallback& callback);
 
@@ -236,7 +236,7 @@ class WEBKIT_STORAGE_EXPORT LocalFileSyncContext
       const SyncFileMetadataCallback& callback,
       base::PlatformFileError file_error,
       const base::PlatformFileInfo& file_info,
-      const FilePath& platform_path);
+      const base::FilePath& platform_path);
 
   base::TimeDelta NotifyChangesDuration();
 
diff --git a/webkit/fileapi/syncable/local_file_sync_context_unittest.cc b/webkit/fileapi/syncable/local_file_sync_context_unittest.cc
index 0f2ad440964620..4cb59c708f70cd 100644
--- a/webkit/fileapi/syncable/local_file_sync_context_unittest.cc
+++ b/webkit/fileapi/syncable/local_file_sync_context_unittest.cc
@@ -119,7 +119,7 @@ class LocalFileSyncContextTest : public testing::Test {
 
   SyncStatusCode ApplyRemoteChange(FileSystemContext* file_system_context,
                                    const FileChange& change,
-                                   const FilePath& local_path,
+                                   const base::FilePath& local_path,
                                    const FileSystemURL& url,
                                    SyncFileType expected_file_type) {
     SCOPED_TRACE(testing::Message() << "ApplyChange for " <<
@@ -431,7 +431,7 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForDeletion) {
                     SYNC_FILE_TYPE_FILE);
   EXPECT_EQ(SYNC_STATUS_OK,
             ApplyRemoteChange(file_system.file_system_context(),
-                              change, FilePath(), kFile,
+                              change, base::FilePath(), kFile,
                               SYNC_FILE_TYPE_FILE));
 
   // The implementation doesn't check file type for deletion, and it must be ok
@@ -439,7 +439,7 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForDeletion) {
   change = FileChange(FileChange::FILE_CHANGE_DELETE, SYNC_FILE_TYPE_UNKNOWN);
   EXPECT_EQ(SYNC_STATUS_OK,
             ApplyRemoteChange(file_system.file_system_context(),
-                              change, FilePath(), kDir,
+                              change, base::FilePath(), kDir,
                               SYNC_FILE_TYPE_DIRECTORY));
 
   // Check the directory/files are deleted successfully.
@@ -506,8 +506,8 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForAddOrUpdate) {
   file_system.ClearChangeForURLInTracker(*urls.begin());
 
   // Prepare temporary files which represent the remote file data.
-  const FilePath kFilePath1(temp_dir.path().Append(FPL("file1")));
-  const FilePath kFilePath2(temp_dir.path().Append(FPL("file2")));
+  const base::FilePath kFilePath1(temp_dir.path().Append(FPL("file1")));
+  const base::FilePath kFilePath2(temp_dir.path().Append(FPL("file2")));
 
   ASSERT_EQ(static_cast<int>(arraysize(kTestFileData1) - 1),
             file_util::WriteFile(kFilePath1, kTestFileData1,
@@ -565,7 +565,7 @@ TEST_F(LocalFileSyncContextTest, ApplyRemoteChangeForAddOrUpdate) {
                       SYNC_FILE_TYPE_DIRECTORY);
   EXPECT_EQ(SYNC_STATUS_OK,
             ApplyRemoteChange(file_system.file_system_context(),
-                              change, FilePath(), kDir,
+                              change, base::FilePath(), kDir,
                               SYNC_FILE_TYPE_UNKNOWN));
 
   // This should not happen, but calling ApplyRemoteChange
diff --git a/webkit/fileapi/syncable/sync_file_metadata.h b/webkit/fileapi/syncable/sync_file_metadata.h
index 266241fd8b3092..097c3776cc55a0 100644
--- a/webkit/fileapi/syncable/sync_file_metadata.h
+++ b/webkit/fileapi/syncable/sync_file_metadata.h
@@ -43,7 +43,7 @@ struct WEBKIT_STORAGE_EXPORT LocalFileSyncInfo {
   ~LocalFileSyncInfo();
 
   FileSystemURL url;
-  FilePath local_file_path;
+  base::FilePath local_file_path;
   SyncFileMetadata metadata;
   FileChangeList changes;
 };
diff --git a/webkit/fileapi/syncable/syncable_file_system_operation.cc b/webkit/fileapi/syncable/syncable_file_system_operation.cc
index 03875357c6ce69..e2145b5c678ba6 100644
--- a/webkit/fileapi/syncable/syncable_file_system_operation.cc
+++ b/webkit/fileapi/syncable/syncable_file_system_operation.cc
@@ -183,7 +183,7 @@ void SyncableFileSystemOperation::GetMetadata(
   DCHECK(CalledOnValidThread());
   if (!operation_runner_) {
     callback.Run(base::PLATFORM_FILE_ERROR_NOT_FOUND,
-                 base::PlatformFileInfo(), FilePath());
+                 base::PlatformFileInfo(), base::FilePath());
     delete file_system_operation_;
     delete this;
     return;
@@ -330,7 +330,7 @@ void SyncableFileSystemOperation::CreateSnapshotFile(
   DCHECK(CalledOnValidThread());
   if (!operation_runner_) {
     callback.Run(base::PLATFORM_FILE_ERROR_NOT_FOUND,
-                 base::PlatformFileInfo(), FilePath(), NULL);
+                 base::PlatformFileInfo(), base::FilePath(), NULL);
     delete file_system_operation_;
     delete this;
     return;
diff --git a/webkit/fileapi/syncable/syncable_file_system_util.cc b/webkit/fileapi/syncable/syncable_file_system_util.cc
index e8d87d9f869d27..efb91224d7d44f 100644
--- a/webkit/fileapi/syncable/syncable_file_system_util.cc
+++ b/webkit/fileapi/syncable/syncable_file_system_util.cc
@@ -14,7 +14,7 @@ namespace fileapi {
 
 bool RegisterSyncableFileSystem(const std::string& service_name) {
   return ExternalMountPoints::GetSystemInstance()->RegisterFileSystem(
-      service_name, kFileSystemTypeSyncable, FilePath());
+      service_name, kFileSystemTypeSyncable, base::FilePath());
 }
 
 bool RevokeSyncableFileSystem(const std::string& service_name) {
@@ -33,11 +33,11 @@ GURL GetSyncableFileSystemRootURI(const GURL& origin,
 
 FileSystemURL CreateSyncableFileSystemURL(const GURL& origin,
                                           const std::string& service_name,
-                                          const FilePath& path) {
+                                          const base::FilePath& path) {
   return ExternalMountPoints::GetSystemInstance()->CreateCrackedFileSystemURL(
       origin,
       kFileSystemTypeExternal,
-      FilePath::FromUTF8Unsafe(service_name).Append(path));
+      base::FilePath::FromUTF8Unsafe(service_name).Append(path));
 }
 
 bool SerializeSyncableFileSystemURL(const FileSystemURL& url,
diff --git a/webkit/fileapi/syncable/syncable_file_system_util.h b/webkit/fileapi/syncable/syncable_file_system_util.h
index 439a086bf7b39c..542856c094ddd3 100644
--- a/webkit/fileapi/syncable/syncable_file_system_util.h
+++ b/webkit/fileapi/syncable/syncable_file_system_util.h
@@ -38,7 +38,8 @@ WEBKIT_STORAGE_EXPORT GURL GetSyncableFileSystemRootURI(
 //   path: '/foo/bar',
 // returns 'filesystem:http://www.example.com/external/service_name/foo/bar'
 WEBKIT_STORAGE_EXPORT FileSystemURL CreateSyncableFileSystemURL(
-    const GURL& origin, const std::string& service_name, const FilePath& path);
+    const GURL& origin, const std::string& service_name,
+    const base::FilePath& path);
 
 // Serializes a given FileSystemURL |url| and sets the serialized string to
 // |serialized_url|. If the URL does not represent a syncable filesystem,
diff --git a/webkit/fileapi/syncable/syncable_file_system_util_unittest.cc b/webkit/fileapi/syncable/syncable_file_system_util_unittest.cc
index 91b0baab3ecc63..6e8dcc0c1f3f3c 100644
--- a/webkit/fileapi/syncable/syncable_file_system_util_unittest.cc
+++ b/webkit/fileapi/syncable/syncable_file_system_util_unittest.cc
@@ -25,14 +25,14 @@ const char kNonSyncableFileSystemRootURI[] =
 
 const char kOrigin[] = "http://www.example.com/";
 const char kServiceName[] = "service";
-const FilePath::CharType kPath[] = FILE_PATH_LITERAL("dir/file");
+const base::FilePath::CharType kPath[] = FILE_PATH_LITERAL("dir/file");
 
 FileSystemURL CreateFileSystemURL(const std::string& url) {
   return ExternalMountPoints::GetSystemInstance()->CrackURL(GURL(url));
 }
 
-FilePath CreateNormalizedFilePath(const FilePath::CharType* path) {
-  return FilePath(path).NormalizePathSeparators();
+base::FilePath CreateNormalizedFilePath(const base::FilePath::CharType* path) {
+  return base::FilePath(path).NormalizePathSeparators();
 }
 
 }  // namespace
@@ -45,9 +45,9 @@ TEST(SyncableFileSystemUtilTest, GetSyncableFileSystemRootURI) {
 
 TEST(SyncableFileSystemUtilTest, CreateSyncableFileSystemURL) {
   ScopedExternalFileSystem scoped_fs(
-      kServiceName, kFileSystemTypeSyncable, FilePath());
+      kServiceName, kFileSystemTypeSyncable, base::FilePath());
 
-  const FilePath path(kPath);
+  const base::FilePath path(kPath);
   const FileSystemURL expected_url =
       CreateFileSystemURL(kSyncableFileSystemRootURI + path.AsUTF8Unsafe());
   const FileSystemURL url =
@@ -60,13 +60,13 @@ TEST(SyncableFileSystemUtilTest, CreateSyncableFileSystemURL) {
 TEST(SyncableFileSystemUtilTest,
        SerializeAndDesirializeSyncableFileSystemURL) {
   ScopedExternalFileSystem scoped_fs(
-      kServiceName, kFileSystemTypeSyncable, FilePath());
+      kServiceName, kFileSystemTypeSyncable, base::FilePath());
 
   const std::string expected_url_str = kSyncableFileSystemRootURI +
       CreateNormalizedFilePath(kPath).AsUTF8Unsafe();
   const FileSystemURL expected_url = CreateFileSystemURL(expected_url_str);
   const FileSystemURL url =
-      CreateSyncableFileSystemURL(GURL(kOrigin), kServiceName, FilePath(kPath));
+      CreateSyncableFileSystemURL(GURL(kOrigin), kServiceName, base::FilePath(kPath));
 
   std::string serialized;
   EXPECT_TRUE(SerializeSyncableFileSystemURL(url, &serialized));
@@ -81,9 +81,9 @@ TEST(SyncableFileSystemUtilTest,
 TEST(SyncableFileSystemUtilTest,
      FailInSerializingAndDeserializingSyncableFileSystemURL) {
   ScopedExternalFileSystem scoped_fs(
-      kServiceName, kFileSystemTypeSyncable, FilePath());
+      kServiceName, kFileSystemTypeSyncable, base::FilePath());
 
-  const FilePath normalized_path = CreateNormalizedFilePath(kPath);
+  const base::FilePath normalized_path = CreateNormalizedFilePath(kPath);
   const std::string non_registered_url =
       kNonRegisteredFileSystemRootURI + normalized_path.AsUTF8Unsafe();
   const std::string non_syncable_url =
diff --git a/webkit/fileapi/test_file_set.cc b/webkit/fileapi/test_file_set.cc
index 6d30f74eec705e..96213f1ee4128f 100644
--- a/webkit/fileapi/test_file_set.cc
+++ b/webkit/fileapi/test_file_set.cc
@@ -39,9 +39,9 @@ const TestCaseRecord kRegularTestCases[] = {
 
 const size_t kRegularTestCaseSize = arraysize(kRegularTestCases);
 
-void SetUpOneTestCase(const FilePath& root_path,
+void SetUpOneTestCase(const base::FilePath& root_path,
                       const TestCaseRecord& test_case) {
-  FilePath path = root_path.Append(test_case.path);
+  base::FilePath path = root_path.Append(test_case.path);
   if (test_case.is_directory) {
     ASSERT_TRUE(file_util::CreateDirectory(path));
     return;
@@ -64,7 +64,7 @@ void SetUpOneTestCase(const FilePath& root_path,
 }
 
 
-void SetUpRegularTestCases(const FilePath& root_path) {
+void SetUpRegularTestCases(const base::FilePath& root_path) {
   for (size_t i = 0; i < arraysize(kRegularTestCases); ++i) {
     SCOPED_TRACE(testing::Message() << "Creating kRegularTestCases " << i);
     SetUpOneTestCase(root_path, kRegularTestCases[i]);
diff --git a/webkit/fileapi/test_file_set.h b/webkit/fileapi/test_file_set.h
index 75673c9fa29beb..6823c6d1f9c7f6 100644
--- a/webkit/fileapi/test_file_set.h
+++ b/webkit/fileapi/test_file_set.h
@@ -19,7 +19,7 @@ namespace test {
 
 struct TestCaseRecord {
   bool is_directory;
-  const FilePath::CharType path[64];
+  const base::FilePath::CharType path[64];
   int64 data_file_size;
 };
 
@@ -29,10 +29,10 @@ extern const size_t kRegularTestCaseSize;
 size_t GetRegularTestCaseSize();
 
 // Creates one file or directory specified by |record|.
-void SetUpOneTestCase(const FilePath& root_path, const TestCaseRecord& record);
+void SetUpOneTestCase(const base::FilePath& root_path, const TestCaseRecord& record);
 
 // Creates the files and directories specified in kRegularTestCases.
-void SetUpRegularTestCases(const FilePath& root_path);
+void SetUpRegularTestCases(const base::FilePath& root_path);
 
 }  // namespace test
 
diff --git a/webkit/fileapi/test_mount_point_provider.cc b/webkit/fileapi/test_mount_point_provider.cc
index d062763fbbc28f..25b1630f4464fb 100644
--- a/webkit/fileapi/test_mount_point_provider.cc
+++ b/webkit/fileapi/test_mount_point_provider.cc
@@ -66,7 +66,7 @@ class TestMountPointProvider::QuotaUtil
 
 TestMountPointProvider::TestMountPointProvider(
     base::SequencedTaskRunner* task_runner,
-    const FilePath& base_path)
+    const base::FilePath& base_path)
     : base_path_(base_path),
       task_runner_(task_runner),
       local_file_util_(new AsyncFileUtilAdapter(new LocalFileUtil())),
@@ -89,7 +89,7 @@ void TestMountPointProvider::ValidateFileSystemRoot(
   NOTREACHED();
 }
 
-FilePath TestMountPointProvider::GetFileSystemRootPathOnFileThread(
+base::FilePath TestMountPointProvider::GetFileSystemRootPathOnFileThread(
     const FileSystemURL& url,
     bool create) {
   DCHECK_EQ(kFileSystemTypeTest, url.type());
@@ -98,7 +98,7 @@ FilePath TestMountPointProvider::GetFileSystemRootPathOnFileThread(
     success = file_util::CreateDirectory(base_path_);
   else
     success = file_util::DirectoryExists(base_path_);
-  return success ? base_path_ : FilePath();
+  return success ? base_path_ : base::FilePath();
 }
 
 bool TestMountPointProvider::IsAccessAllowed(const FileSystemURL& url) {
@@ -106,7 +106,7 @@ bool TestMountPointProvider::IsAccessAllowed(const FileSystemURL& url) {
 }
 
 bool TestMountPointProvider::IsRestrictedFileName(
-    const FilePath& filename) const {
+    const base::FilePath& filename) const {
   return false;
 }
 
diff --git a/webkit/fileapi/test_mount_point_provider.h b/webkit/fileapi/test_mount_point_provider.h
index 4bee1025af8b98..29a461408f5626 100644
--- a/webkit/fileapi/test_mount_point_provider.h
+++ b/webkit/fileapi/test_mount_point_provider.h
@@ -30,7 +30,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE TestMountPointProvider
  public:
   TestMountPointProvider(
       base::SequencedTaskRunner* task_runner,
-      const FilePath& base_path);
+      const base::FilePath& base_path);
   virtual ~TestMountPointProvider();
 
   // FileSystemMountPointProvider implementation.
@@ -39,11 +39,11 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE TestMountPointProvider
       FileSystemType type,
       bool create,
       const ValidateFileSystemCallback& callback) OVERRIDE;
-  virtual FilePath GetFileSystemRootPathOnFileThread(
+  virtual base::FilePath GetFileSystemRootPathOnFileThread(
       const FileSystemURL& url,
       bool create) OVERRIDE;
   virtual bool IsAccessAllowed(const FileSystemURL& url) OVERRIDE;
-  virtual bool IsRestrictedFileName(const FilePath& filename) const OVERRIDE;
+  virtual bool IsRestrictedFileName(const base::FilePath& filename) const OVERRIDE;
   virtual FileSystemFileUtil* GetFileUtil(FileSystemType type) OVERRIDE;
   virtual AsyncFileUtil* GetAsyncFileUtil(FileSystemType type) OVERRIDE;
   virtual FilePermissionPolicy GetPermissionPolicy(
@@ -74,7 +74,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE TestMountPointProvider
  private:
   class QuotaUtil;
 
-  FilePath base_path_;
+  base::FilePath base_path_;
   scoped_refptr<base::SequencedTaskRunner> task_runner_;
   scoped_ptr<AsyncFileUtilAdapter> local_file_util_;
   scoped_ptr<QuotaUtil> quota_util_;
diff --git a/webkit/fileapi/upload_file_system_file_element_reader_unittest.cc b/webkit/fileapi/upload_file_system_file_element_reader_unittest.cc
index 4d9c7befb4b8e3..d9ea38352957ab 100644
--- a/webkit/fileapi/upload_file_system_file_element_reader_unittest.cc
+++ b/webkit/fileapi/upload_file_system_file_element_reader_unittest.cc
@@ -85,7 +85,7 @@ class UploadFileSystemFileElementReaderTest : public testing::Test {
         file_system_context_->CreateCrackedFileSystemURL(
             GURL(kFileSystemURLOrigin),
             kFileSystemType,
-            FilePath().AppendASCII(filename));
+            base::FilePath().AppendASCII(filename));
 
     fileapi::FileSystemFileUtil* file_util =
         file_system_context_->GetFileUtil(kFileSystemType);
@@ -108,7 +108,7 @@ class UploadFileSystemFileElementReaderTest : public testing::Test {
     base::ClosePlatformFile(handle);
 
     base::PlatformFileInfo file_info;
-    FilePath platform_path;
+    base::FilePath platform_path;
     ASSERT_EQ(base::PLATFORM_FILE_OK,
               file_util->GetFileInfo(&context, url, &file_info,
                                      &platform_path));
diff --git a/webkit/glue/dom_operations_unittest.cc b/webkit/glue/dom_operations_unittest.cc
index 05aeb760d5e590..141a819fdc5693 100644
--- a/webkit/glue/dom_operations_unittest.cc
+++ b/webkit/glue/dom_operations_unittest.cc
@@ -20,7 +20,7 @@ class DomOperationsTests : public TestShellTest {
   // Test function GetAllSavableResourceLinksForCurrentPage with a web page.
   // We expect result of GetAllSavableResourceLinksForCurrentPage exactly
   // matches expected_resources_set.
-  void GetSavableResourceLinksForPage(const FilePath& page_file_path,
+  void GetSavableResourceLinksForPage(const base::FilePath& page_file_path,
       const std::set<GURL>& expected_resources_set);
 
  protected:
@@ -36,7 +36,7 @@ class DomOperationsTests : public TestShellTest {
 
 
 void DomOperationsTests::GetSavableResourceLinksForPage(
-    const FilePath& page_file_path,
+    const base::FilePath& page_file_path,
     const std::set<GURL>& expected_resources_set) {
   // Convert local file path to file URL.
   GURL file_url = net::FilePathToFileURL(page_file_path);
@@ -82,7 +82,7 @@ void DomOperationsTests::GetSavableResourceLinksForPage(
 TEST_F(DomOperationsTests, GetSavableResourceLinksWithPageHasValidLinks) {
   std::set<GURL> expected_resources_set;
   // Set directory of test data.
-  FilePath page_file_path = data_dir_.AppendASCII("dom_serializer");
+  base::FilePath page_file_path = data_dir_.AppendASCII("dom_serializer");
 
   const char* expected_sub_resource_links[] = {
     "file:///c:/yt/css/base_all-vfl36460.css",
@@ -98,7 +98,7 @@ TEST_F(DomOperationsTests, GetSavableResourceLinksWithPageHasValidLinks) {
     expected_resources_set.insert(GURL(expected_sub_resource_links[i]));
   // Add all expected links of frame to expected set.
   for (size_t i = 0; i < arraysize(expected_frame_links); ++i) {
-    const FilePath expected_frame_url =
+    const base::FilePath expected_frame_url =
         page_file_path.AppendASCII(expected_frame_links[i]);
     expected_resources_set.insert(
         net::FilePathToFileURL(expected_frame_url));
@@ -113,14 +113,14 @@ TEST_F(DomOperationsTests, GetSavableResourceLinksWithPageHasValidLinks) {
 TEST_F(DomOperationsTests, GetSavableResourceLinksWithPageHasInvalidLinks) {
   std::set<GURL> expected_resources_set;
   // Set directory of test data.
-  FilePath page_file_path = data_dir_.AppendASCII("dom_serializer");
+  base::FilePath page_file_path = data_dir_.AppendASCII("dom_serializer");
 
   const char* expected_frame_links[] = {
     "youtube_2.htm"
   };
   // Add all expected links of frame to expected set.
   for (size_t i = 0; i < arraysize(expected_frame_links); ++i) {
-    FilePath expected_frame_url =
+    base::FilePath expected_frame_url =
         page_file_path.AppendASCII(expected_frame_links[i]);
     expected_resources_set.insert(
         net::FilePathToFileURL(expected_frame_url));
diff --git a/webkit/glue/dom_serializer_unittest.cc b/webkit/glue/dom_serializer_unittest.cc
index 7097deffbe6a1a..de4f8a4d13d5b9 100644
--- a/webkit/glue/dom_serializer_unittest.cc
+++ b/webkit/glue/dom_serializer_unittest.cc
@@ -205,7 +205,7 @@ class DomSerializerTests : public TestShellTest,
   WebVector<WebString> local_paths_;
   // The local_directory_name_ is dummy relative path of directory which
   // contain all saved auxiliary files included all sub frames and resources.
-  const FilePath local_directory_name_;
+  const base::FilePath local_directory_name_;
 
  protected:
   // testing::Test
@@ -283,7 +283,7 @@ bool IsMetaElement(const WebNode& node, std::string& charset_info) {
 // If original contents have document type, the serialized contents also have
 // document type.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithDocType) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("youtube_1.htm");
   GURL file_url = net::FilePathToFileURL(page_file_path);
@@ -312,7 +312,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithDocType) {
 // If original contents do not have document type, the serialized contents
 // also do not have document type.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithoutDocType) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("youtube_2.htm");
   GURL file_url = net::FilePathToFileURL(page_file_path);
@@ -342,7 +342,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithoutDocType) {
 // finishing serialization, the serialized contents should be same
 // with original XML document.
 TEST_F(DomSerializerTests, SerializeXMLDocWithBuiltInEntities) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("note.xml");
   // Read original contents for later comparison.
@@ -364,7 +364,7 @@ TEST_F(DomSerializerTests, SerializeXMLDocWithBuiltInEntities) {
 
 // When serializing DOM, we add MOTW declaration before html tag.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithAddingMOTW) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("youtube_2.htm");
   // Read original contents for later comparison .
@@ -398,7 +398,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithAddingMOTW) {
 // http://bugs.webkit.org/show_bug.cgi?id=16621 even the original document
 // does not have META charset declaration.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithNoMetaCharsetInOriginalDoc) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("youtube_1.htm");
   // Get file URL.
@@ -462,7 +462,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithNoMetaCharsetInOriginalDoc) {
 // declarations.
 TEST_F(DomSerializerTests,
        SerializeHTMLDOMWithMultipleMetaCharsetInOriginalDoc) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("youtube_2.htm");
   // Get file URL.
@@ -527,7 +527,7 @@ TEST_F(DomSerializerTests,
 
 // Test situation of html entities in text when serializing HTML DOM.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithEntitiesInText) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII(
       "dom_serializer/htmlentities_in_text.htm");
   // Get file URL. The URL is dummy URL to identify the following loading
@@ -587,7 +587,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithEntitiesInText) {
 // HTML DOM.
 // This test started to fail at WebKit r65388. See http://crbug.com/52279.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithEntitiesInAttributeValue) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII(
       "dom_serializer/htmlentities_in_attribute_value.htm");
   // Get file URL. The URL is dummy URL to identify the following loading
@@ -638,7 +638,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithEntitiesInAttributeValue) {
 // This test started to fail at WebKit r65351. See http://crbug.com/52279.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithNonStandardEntities) {
   // Make a test file URL and load it.
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("nonstandard_htmlentities.htm");
   GURL file_url = net::FilePathToFileURL(page_file_path);
@@ -678,7 +678,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithBaseTag) {
   // There are total 2 available base tags in this test file.
   const int kTotalBaseTagCountInTestFile = 2;
 
-  FilePath page_file_path = data_dir_.AppendASCII("dom_serializer");
+  base::FilePath page_file_path = data_dir_.AppendASCII("dom_serializer");
   file_util::EnsureEndsWithSeparator(&page_file_path);
 
   // Get page dir URL which is base URL of this file.
@@ -782,7 +782,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithBaseTag) {
 
 // Serializing page which has an empty HEAD tag.
 TEST_F(DomSerializerTests, SerializeHTMLDOMWithEmptyHead) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("empty_head.htm");
   GURL file_url = net::FilePathToFileURL(page_file_path);
@@ -842,7 +842,7 @@ TEST_F(DomSerializerTests, SerializeHTMLDOMWithEmptyHead) {
 // Test that we don't crash when the page contains an iframe that
 // was handled as a download (http://crbug.com/42212).
 TEST_F(DomSerializerTests, SerializeDocumentWithDownloadedIFrame) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("iframe-src-is-exe.htm");
   GURL file_url = net::FilePathToFileURL(page_file_path);
@@ -854,7 +854,7 @@ TEST_F(DomSerializerTests, SerializeDocumentWithDownloadedIFrame) {
 }
 
 TEST_F(DomSerializerTests, SubResourceForElementsInNonHTMLNamespace) {
-  FilePath page_file_path = data_dir_;
+  base::FilePath page_file_path = data_dir_;
   page_file_path = page_file_path.AppendASCII("dom_serializer");
   page_file_path = page_file_path.AppendASCII("non_html_namespace.htm");
   GURL file_url = net::FilePathToFileURL(page_file_path);
diff --git a/webkit/glue/glue_serialize.cc b/webkit/glue/glue_serialize.cc
index 3fad842b913056..e9d3ae4bc8f938 100644
--- a/webkit/glue/glue_serialize.cc
+++ b/webkit/glue/glue_serialize.cc
@@ -509,9 +509,9 @@ WebHistoryItem HistoryItemFromString(const std::string& serialized_item) {
   return HistoryItemFromString(serialized_item, ALWAYS_INCLUDE_FORM_DATA, true);
 }
 
-std::vector<FilePath> FilePathsFromHistoryState(
+std::vector<base::FilePath> FilePathsFromHistoryState(
     const std::string& content_state) {
-  std::vector<FilePath> to_return;
+  std::vector<base::FilePath> to_return;
   // TODO(darin): We should avoid using the WebKit API here, so that we do not
   // need to have WebKit initialized before calling this method.
   const WebHistoryItem& item =
diff --git a/webkit/glue/glue_serialize.h b/webkit/glue/glue_serialize.h
index ac869a9941a0cc..38df965758bc36 100644
--- a/webkit/glue/glue_serialize.h
+++ b/webkit/glue/glue_serialize.h
@@ -28,7 +28,7 @@ WEBKIT_GLUE_EXPORT WebKit::WebHistoryItem HistoryItemFromString(
 
 // Reads file paths from the HTTP body and the file input elements of a
 // serialized WebHistoryItem.
-WEBKIT_GLUE_EXPORT std::vector<FilePath> FilePathsFromHistoryState(
+WEBKIT_GLUE_EXPORT std::vector<base::FilePath> FilePathsFromHistoryState(
     const std::string& content_state);
 
 // For testing purposes only.
diff --git a/webkit/glue/glue_serialize_unittest.cc b/webkit/glue/glue_serialize_unittest.cc
index 91916efa46e306..250dceac0304b0 100644
--- a/webkit/glue/glue_serialize_unittest.cc
+++ b/webkit/glue/glue_serialize_unittest.cc
@@ -265,8 +265,8 @@ TEST_F(GlueSerializeTest, FilePathsFromHistoryState) {
   WebHistoryItem item = MakeHistoryItem(false, true);
 
   // Append file paths to item.
-  FilePath file_path1(FILE_PATH_LITERAL("file.txt"));
-  FilePath file_path2(FILE_PATH_LITERAL("another_file"));
+  base::FilePath file_path1(FILE_PATH_LITERAL("file.txt"));
+  base::FilePath file_path2(FILE_PATH_LITERAL("another_file"));
   WebHTTPBody http_body;
   http_body.initialize();
   http_body.appendFile(webkit_base::FilePathToWebString(file_path1));
@@ -274,7 +274,7 @@ TEST_F(GlueSerializeTest, FilePathsFromHistoryState) {
   item.setHTTPBody(http_body);
 
   std::string serialized_item = webkit_glue::HistoryItemToString(item);
-  const std::vector<FilePath>& file_paths =
+  const std::vector<base::FilePath>& file_paths =
       webkit_glue::FilePathsFromHistoryState(serialized_item);
   ASSERT_EQ(2U, file_paths.size());
   EXPECT_EQ(file_path1, file_paths[0]);
diff --git a/webkit/glue/resource_loader_bridge.h b/webkit/glue/resource_loader_bridge.h
index 52859b3c946230..d20040fc88a44e 100644
--- a/webkit/glue/resource_loader_bridge.h
+++ b/webkit/glue/resource_loader_bridge.h
@@ -181,7 +181,7 @@ struct ResourceResponseInfo {
   // The path to a file that will contain the response body.  It may only
   // contain a portion of the response body at the time that the ResponseInfo
   // becomes available.
-  FilePath download_file_path;
+  base::FilePath download_file_path;
 
   // True if the response was delivered using SPDY.
   bool was_fetched_via_spdy;
diff --git a/webkit/glue/resource_request_body.cc b/webkit/glue/resource_request_body.cc
index eb820fca883cdd..763c7d07d95d2e 100644
--- a/webkit/glue/resource_request_body.cc
+++ b/webkit/glue/resource_request_body.cc
@@ -73,7 +73,7 @@ void ResourceRequestBody::AppendBytes(const char* bytes, int bytes_len) {
 }
 
 void ResourceRequestBody::AppendFileRange(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     uint64 offset, uint64 length,
     const base::Time& expected_modification_time) {
   elements_.push_back(Element());
diff --git a/webkit/glue/resource_request_body.h b/webkit/glue/resource_request_body.h
index 8331bdf21d0e75..71a049577c389d 100644
--- a/webkit/glue/resource_request_body.h
+++ b/webkit/glue/resource_request_body.h
@@ -14,6 +14,7 @@
 #include "webkit/glue/webkit_glue_export.h"
 
 namespace base {
+class FilePath;
 class TaskRunner;
 }
 
@@ -42,7 +43,7 @@ class WEBKIT_GLUE_EXPORT ResourceRequestBody
   ResourceRequestBody();
 
   void AppendBytes(const char* bytes, int bytes_len);
-  void AppendFileRange(const FilePath& file_path,
+  void AppendFileRange(const base::FilePath& file_path,
                        uint64 offset, uint64 length,
                        const base::Time& expected_modification_time);
   void AppendBlob(const GURL& blob_url);
diff --git a/webkit/glue/resource_request_body_unittest.cc b/webkit/glue/resource_request_body_unittest.cc
index 62c5d703c77a47..c596739e4976dc 100644
--- a/webkit/glue/resource_request_body_unittest.cc
+++ b/webkit/glue/resource_request_body_unittest.cc
@@ -59,14 +59,14 @@ TEST(ResourceRequestBodyTest, CreateUploadDataStreamWithoutBlob) {
   scoped_refptr<ResourceRequestBody> request_body = new ResourceRequestBody;
 
   const char kData[] = "123";
-  const FilePath::StringType kFilePath = FILE_PATH_LITERAL("abc");
+  const base::FilePath::StringType kFilePath = FILE_PATH_LITERAL("abc");
   const uint64 kFileOffset = 10U;
   const uint64 kFileLength = 100U;
   const base::Time kFileTime = base::Time::FromDoubleT(999);
   const int64 kIdentifier = 12345;
 
   request_body->AppendBytes(kData, arraysize(kData) - 1);
-  request_body->AppendFileRange(FilePath(kFilePath),
+  request_body->AppendFileRange(base::FilePath(kFilePath),
                                 kFileOffset, kFileLength, kFileTime);
   request_body->set_identifier(kIdentifier);
 
@@ -106,7 +106,7 @@ TEST(ResourceRequestBodyTest, ResolveBlobAndCreateUploadDataStream) {
 
   blob_data->AppendData("BlobData");
   blob_data->AppendFile(
-      FilePath(FILE_PATH_LITERAL("BlobFile.txt")), 0, 20, time1);
+      base::FilePath(FILE_PATH_LITERAL("BlobFile.txt")), 0, 20, time1);
 
   GURL blob_url1("blob://url_1");
   blob_storage_controller.AddFinishedBlob(blob_url1, blob_data);
@@ -132,7 +132,7 @@ TEST(ResourceRequestBodyTest, ResolveBlobAndCreateUploadDataStream) {
   ResourceRequestBody::Element upload_element1, upload_element2;
   upload_element1.SetToBytes("Hello", 5);
   upload_element2.SetToFilePathRange(
-      FilePath(FILE_PATH_LITERAL("foo1.txt")), 0, 20, time2);
+      base::FilePath(FILE_PATH_LITERAL("foo1.txt")), 0, 20, time2);
 
   // Test no blob reference.
   scoped_refptr<ResourceRequestBody> request_body(new ResourceRequestBody());
diff --git a/webkit/glue/simple_webmimeregistry_impl.cc b/webkit/glue/simple_webmimeregistry_impl.cc
index 98473ee5ae2bc2..b8e81a8b5c6385 100644
--- a/webkit/glue/simple_webmimeregistry_impl.cc
+++ b/webkit/glue/simple_webmimeregistry_impl.cc
@@ -139,7 +139,7 @@ WebString SimpleWebMimeRegistryImpl::mimeTypeFromFile(
 
 WebString SimpleWebMimeRegistryImpl::preferredExtensionForMIMEType(
     const WebString& mime_type) {
-  FilePath::StringType file_extension;
+  base::FilePath::StringType file_extension;
   net::GetPreferredExtensionForMimeType(ToASCIIOrEmpty(mime_type),
                                         &file_extension);
   return webkit_base::FilePathStringToWebString(file_extension);
diff --git a/webkit/glue/unittest_test_server.h b/webkit/glue/unittest_test_server.h
index 2d5df48a9e7e92..815e62b94aaa17 100644
--- a/webkit/glue/unittest_test_server.h
+++ b/webkit/glue/unittest_test_server.h
@@ -15,7 +15,7 @@ class UnittestTestServer : public net::TestServer {
   UnittestTestServer()
       : net::TestServer(net::TestServer::TYPE_HTTP,
                         net::TestServer::kLocalhost,
-                        FilePath(FILE_PATH_LITERAL("webkit/data"))) {
+                        base::FilePath(FILE_PATH_LITERAL("webkit/data"))) {
   }
 };
 
diff --git a/webkit/glue/web_intent_data.cc b/webkit/glue/web_intent_data.cc
index 0ad55b567be2b7..9df14228ab303a 100644
--- a/webkit/glue/web_intent_data.cc
+++ b/webkit/glue/web_intent_data.cc
@@ -61,7 +61,7 @@ WebIntentData::WebIntentData(const string16& action_in,
 
 WebIntentData::WebIntentData(const string16& action_in,
                              const string16& type_in,
-                             const FilePath& blob_file_in,
+                             const base::FilePath& blob_file_in,
                              int64 blob_length_in)
     : action(action_in),
       type(type_in),
diff --git a/webkit/glue/web_intent_data.h b/webkit/glue/web_intent_data.h
index fe73328d204c93..1d18428da0e215 100644
--- a/webkit/glue/web_intent_data.h
+++ b/webkit/glue/web_intent_data.h
@@ -50,7 +50,7 @@ struct WEBKIT_GLUE_EXPORT WebIntentData {
   // arguments to WebBlob::createFromFile. Note: when mime_data has
   // length==1, this blob will be set as the 'blob' member of the first
   // object in the delivered data payload.
-  FilePath blob_file;
+  base::FilePath blob_file;
   // Length of the blob.
   int64 blob_length;
 
diff --git a/webkit/glue/web_intent_reply_data.cc b/webkit/glue/web_intent_reply_data.cc
index 8a19fefadcc90f..1b30891c006e70 100644
--- a/webkit/glue/web_intent_reply_data.cc
+++ b/webkit/glue/web_intent_reply_data.cc
@@ -22,7 +22,7 @@ WebIntentReply::WebIntentReply(
 
 WebIntentReply::WebIntentReply(
     WebIntentReplyType response_type,
-    FilePath response_data_file,
+    base::FilePath response_data_file,
     int64 response_data_file_length)
     : type(response_type),
       data_file(response_data_file),
diff --git a/webkit/glue/web_intent_reply_data.h b/webkit/glue/web_intent_reply_data.h
index f3bd1720ddf2fa..038c022b78dd15 100644
--- a/webkit/glue/web_intent_reply_data.h
+++ b/webkit/glue/web_intent_reply_data.h
@@ -35,7 +35,7 @@ struct WEBKIT_GLUE_EXPORT WebIntentReply {
   WebIntentReply(WebIntentReplyType type, string16 data);
   WebIntentReply(
       WebIntentReplyType type,
-      FilePath data_file,
+      base::FilePath data_file,
       int64 data_file_size);
 
   bool operator==(const WebIntentReply& other) const;
@@ -47,7 +47,7 @@ struct WEBKIT_GLUE_EXPORT WebIntentReply {
   string16 data;
 
   // FilePath to the data to be delivered. Default value is empty.
-  FilePath data_file;
+  base::FilePath data_file;
 
   // Length of data_path.
   int64 data_file_size;
diff --git a/webkit/glue/web_intent_reply_data_unittest.cc b/webkit/glue/web_intent_reply_data_unittest.cc
index a8aed519e3d851..bf7004cde6c6df 100644
--- a/webkit/glue/web_intent_reply_data_unittest.cc
+++ b/webkit/glue/web_intent_reply_data_unittest.cc
@@ -17,7 +17,7 @@ TEST(WebIntentReplyDataTest, DefaultValues) {
   WebIntentReply reply;
   EXPECT_EQ(webkit_glue::WEB_INTENT_REPLY_INVALID, reply.type);
   EXPECT_EQ(string16(), reply.data);
-  EXPECT_EQ(FilePath(), reply.data_file);
+  EXPECT_EQ(base::FilePath(), reply.data_file);
   EXPECT_EQ(-1, reply.data_file_size);
 }
 
@@ -39,17 +39,17 @@ TEST(WebIntentReplyDataTest, Equality) {
 
   WebIntentReply file_a(
       webkit_glue::WEB_INTENT_REPLY_SUCCESS,
-      FilePath(),
+      base::FilePath(),
       22);
 
   WebIntentReply file_b(
       webkit_glue::WEB_INTENT_REPLY_SUCCESS,
-      FilePath(),
+      base::FilePath(),
       22);
 
   WebIntentReply file_c(
       webkit_glue::WEB_INTENT_REPLY_SUCCESS,
-      FilePath(),
+      base::FilePath(),
       17);
 
   EXPECT_EQ(file_a, file_b);
diff --git a/webkit/glue/webfileutilities_impl.cc b/webkit/glue/webfileutilities_impl.cc
index 3241884a12bbe8..fdf63a12c34163 100644
--- a/webkit/glue/webfileutilities_impl.cc
+++ b/webkit/glue/webfileutilities_impl.cc
@@ -27,7 +27,7 @@ WebFileUtilitiesImpl::~WebFileUtilitiesImpl() {
 }
 
 bool WebFileUtilitiesImpl::fileExists(const WebString& path) {
-  FilePath file_path = webkit_base::WebStringToFilePath(path);
+  base::FilePath file_path = webkit_base::WebStringToFilePath(path);
   return file_util::PathExists(file_path);
 }
 
@@ -58,33 +58,33 @@ bool WebFileUtilitiesImpl::getFileInfo(const WebString& path,
 }
 
 WebString WebFileUtilitiesImpl::directoryName(const WebString& path) {
-  FilePath file_path(webkit_base::WebStringToFilePath(path));
+  base::FilePath file_path(webkit_base::WebStringToFilePath(path));
   return webkit_base::FilePathToWebString(file_path.DirName());
 }
 
 WebString WebFileUtilitiesImpl::pathByAppendingComponent(
     const WebString& webkit_path,
     const WebString& webkit_component) {
-  FilePath path(webkit_base::WebStringToFilePath(webkit_path));
-  FilePath component(webkit_base::WebStringToFilePath(webkit_component));
-  FilePath combined_path = path.Append(component);
+  base::FilePath path(webkit_base::WebStringToFilePath(webkit_path));
+  base::FilePath component(webkit_base::WebStringToFilePath(webkit_component));
+  base::FilePath combined_path = path.Append(component);
   return webkit_base::FilePathStringToWebString(combined_path.value());
 }
 
 bool WebFileUtilitiesImpl::makeAllDirectories(const WebString& path) {
   DCHECK(!sandbox_enabled_);
-  FilePath file_path = webkit_base::WebStringToFilePath(path);
+  base::FilePath file_path = webkit_base::WebStringToFilePath(path);
   return file_util::CreateDirectory(file_path);
 }
 
 WebString WebFileUtilitiesImpl::getAbsolutePath(const WebString& path) {
-  FilePath file_path(webkit_base::WebStringToFilePath(path));
+  base::FilePath file_path(webkit_base::WebStringToFilePath(path));
   file_util::AbsolutePath(&file_path);
   return webkit_base::FilePathStringToWebString(file_path.value());
 }
 
 bool WebFileUtilitiesImpl::isDirectory(const WebString& path) {
-  FilePath file_path(webkit_base::WebStringToFilePath(path));
+  base::FilePath file_path(webkit_base::WebStringToFilePath(path));
   return file_util::DirectoryExists(file_path);
 }
 
diff --git a/webkit/media/crypto/ppapi/clear_key_cdm.cc b/webkit/media/crypto/ppapi/clear_key_cdm.cc
index 7c6eda5fd68f01..2894a52dcb1d3c 100644
--- a/webkit/media/crypto/ppapi/clear_key_cdm.cc
+++ b/webkit/media/crypto/ppapi/clear_key_cdm.cc
@@ -50,7 +50,7 @@ static base::AtExitManager g_at_exit_manager;
 // are required for running in the sandbox, and should no longer be required
 // after http://crbug.com/91970 is fixed.
 static bool InitializeFFmpegLibraries() {
-  FilePath file_path;
+  base::FilePath file_path;
   CHECK(PathService::Get(base::DIR_EXE, &file_path));
   CHECK(media::InitializeMediaLibrary(file_path));
   return true;
diff --git a/webkit/mocks/mock_resource_loader_bridge.h b/webkit/mocks/mock_resource_loader_bridge.h
index 5be7d89ff18fe0..3af75a7c2f16f6 100644
--- a/webkit/mocks/mock_resource_loader_bridge.h
+++ b/webkit/mocks/mock_resource_loader_bridge.h
@@ -8,7 +8,9 @@
 #include "testing/gmock/include/gmock/gmock.h"
 #include "webkit/glue/resource_loader_bridge.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace webkit_glue {
 
@@ -23,7 +25,7 @@ class MockResourceLoaderBridge : public webkit_glue::ResourceLoaderBridge {
 
   MOCK_METHOD2(AppendDataToUpload, void(const char* data, int data_len));
   MOCK_METHOD4(AppendFileRangeToUpload,
-               void(const FilePath& file_path,
+               void(const base::FilePath& file_path,
                     uint64 offset,
                     uint64 length,
                     const base::Time& expected_modification_time));
diff --git a/webkit/plugins/npapi/plugin_host.cc b/webkit/plugins/npapi/plugin_host.cc
index a54c0ba391010a..5cea951adfcd7f 100644
--- a/webkit/plugins/npapi/plugin_host.cc
+++ b/webkit/plugins/npapi/plugin_host.cc
@@ -467,14 +467,14 @@ static NPError PostURLNotify(NPP id,
       return NPERR_FILE_NOT_FOUND;
 
     std::string file_path_ascii(buf);
-    FilePath file_path;
+    base::FilePath file_path;
     static const char kFileUrlPrefix[] = "file:";
     if (StartsWithASCII(file_path_ascii, kFileUrlPrefix, false)) {
       GURL file_url(file_path_ascii);
       DCHECK(file_url.SchemeIsFile());
       net::FileURLToFilePath(file_url, &file_path);
     } else {
-      file_path = FilePath::FromWStringHack(
+      file_path = base::FilePath::FromWStringHack(
           base::SysNativeMBToWide(file_path_ascii));
     }
 
diff --git a/webkit/plugins/npapi/plugin_instance.cc b/webkit/plugins/npapi/plugin_instance.cc
index f26cbec67e55ab..4d49a05dc378a7 100644
--- a/webkit/plugins/npapi/plugin_instance.cc
+++ b/webkit/plugins/npapi/plugin_instance.cc
@@ -315,7 +315,7 @@ void PluginInstance::NPP_StreamAsFile(NPStream *stream, const char *fname) {
   // Creating a temporary FilePath instance on the stack as the explicit
   // FilePath constructor with StringType as an argument causes a compiler
   // error when invoked via vector push back.
-  FilePath file_name = FilePath::FromWStringHack(UTF8ToWide(fname));
+  base::FilePath file_name = base::FilePath::FromWStringHack(UTF8ToWide(fname));
   files_created_.push_back(file_name);
 }
 
diff --git a/webkit/plugins/npapi/plugin_lib.cc b/webkit/plugins/npapi/plugin_lib.cc
index ed01426de04d48..7b927e0a32ac07 100644
--- a/webkit/plugins/npapi/plugin_lib.cc
+++ b/webkit/plugins/npapi/plugin_lib.cc
@@ -23,7 +23,7 @@ const char kPluginInstancesActiveCounter[] = "PluginInstancesActive";
 // A list of all the instantiated plugins.
 static std::vector<scoped_refptr<PluginLib> >* g_loaded_libs;
 
-PluginLib* PluginLib::CreatePluginLib(const FilePath& filename) {
+PluginLib* PluginLib::CreatePluginLib(const base::FilePath& filename) {
   // We can only have one PluginLib object per plugin as it controls the per
   // instance function calls (i.e. NP_Initialize and NP_Shutdown).  So we keep
   // a map of PluginLib objects.
@@ -271,7 +271,7 @@ bool PluginLib::Load() {
 
 // This is a helper to help perform a delayed NP_Shutdown and FreeLibrary on the
 // plugin dll.
-void FreePluginLibraryHelper(const FilePath& path,
+void FreePluginLibraryHelper(const base::FilePath& path,
                              base::NativeLibrary library,
                              NP_ShutdownFunc shutdown_func) {
   if (shutdown_func) {
diff --git a/webkit/plugins/npapi/plugin_lib.h b/webkit/plugins/npapi/plugin_lib.h
index 9051e2dd820e0b..36e9a41a0a77cb 100644
--- a/webkit/plugins/npapi/plugin_lib.h
+++ b/webkit/plugins/npapi/plugin_lib.h
@@ -16,7 +16,9 @@
 #include "webkit/plugins/npapi/webplugin.h"
 #include "webkit/plugins/webkit_plugins_export.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace webkit {
 namespace npapi {
@@ -27,12 +29,12 @@ class PluginInstance;
 // manager for new PluginInstances.
 class WEBKIT_PLUGINS_EXPORT PluginLib : public base::RefCounted<PluginLib> {
  public:
-  static PluginLib* CreatePluginLib(const FilePath& filename);
+  static PluginLib* CreatePluginLib(const base::FilePath& filename);
 
   // Creates a WebPluginInfo structure given a plugin's path.  On success
   // returns true, with the information being put into "info".
   // Returns false if the library couldn't be found, or if it's not a plugin.
-  static bool ReadWebPluginInfo(const FilePath& filename,
+  static bool ReadWebPluginInfo(const base::FilePath& filename,
                                 webkit::WebPluginInfo* info);
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
diff --git a/webkit/plugins/npapi/plugin_lib_mac.mm b/webkit/plugins/npapi/plugin_lib_mac.mm
index d2831008040d36..32e40df91ad353 100644
--- a/webkit/plugins/npapi/plugin_lib_mac.mm
+++ b/webkit/plugins/npapi/plugin_lib_mac.mm
@@ -76,7 +76,7 @@
   }
 }
 
-bool ReadPlistPluginInfo(const FilePath& filename, CFBundleRef bundle,
+bool ReadPlistPluginInfo(const base::FilePath& filename, CFBundleRef bundle,
                          WebPluginInfo* info) {
   NSDictionary* mime_types = GetMIMETypes(bundle);
   if (!mime_types)
@@ -137,7 +137,7 @@ bool ReadPlistPluginInfo(const FilePath& filename, CFBundleRef bundle,
 
 }  // anonymous namespace
 
-bool PluginLib::ReadWebPluginInfo(const FilePath &filename,
+bool PluginLib::ReadWebPluginInfo(const base::FilePath &filename,
                                   WebPluginInfo* info) {
   // There are three ways to get information about plugin capabilities:
   // 1) a set of Info.plist keys, documented at
diff --git a/webkit/plugins/npapi/plugin_lib_posix.cc b/webkit/plugins/npapi/plugin_lib_posix.cc
index cc3ed52c67cd54..144b133c09cad0 100644
--- a/webkit/plugins/npapi/plugin_lib_posix.cc
+++ b/webkit/plugins/npapi/plugin_lib_posix.cc
@@ -42,7 +42,7 @@ enum nsPluginVariable {
 // Read the ELF header and return true if it is usable on
 // the current architecture (e.g. 32-bit ELF on 32-bit build).
 // Returns false on other errors as well.
-bool ELFMatchesCurrentArchitecture(const FilePath& filename) {
+bool ELFMatchesCurrentArchitecture(const base::FilePath& filename) {
   // First make sure we can open the file and it is in fact, a regular file.
   struct stat stat_buf;
   // Open with O_NONBLOCK so we don't block on pipes.
@@ -91,7 +91,7 @@ struct __attribute__((packed)) NSPluginWrapperInfo {
 // if so attempt to unwrap it.  Pass in an opened plugin handle; on
 // success, |dl| and |unwrapped_path| will be filled in with the newly
 // opened plugin.  On failure, params are left unmodified.
-void UnwrapNSPluginWrapper(void **dl, FilePath* unwrapped_path) {
+void UnwrapNSPluginWrapper(void **dl, base::FilePath* unwrapped_path) {
   NSPluginWrapperInfo* info =
       reinterpret_cast<NSPluginWrapperInfo*>(dlsym(*dl, "NPW_Plugin"));
   if (!info)
@@ -107,7 +107,8 @@ void UnwrapNSPluginWrapper(void **dl, FilePath* unwrapped_path) {
                                              sizeof(info->path)));
   if (!path_end)
     path_end = info->path + sizeof(info->path);
-  FilePath path = FilePath(std::string(info->path, path_end - info->path));
+  base::FilePath path = base::FilePath(
+      std::string(info->path, path_end - info->path));
 
   if (!ELFMatchesCurrentArchitecture(path)) {
     LOG(WARNING) << path.value() << " is nspluginwrapper wrapping a "
@@ -139,7 +140,7 @@ void UnwrapNSPluginWrapper(void **dl, FilePath* unwrapped_path) {
 
 }  // namespace
 
-bool PluginLib::ReadWebPluginInfo(const FilePath& filename,
+bool PluginLib::ReadWebPluginInfo(const base::FilePath& filename,
                                   WebPluginInfo* info) {
   // The file to reference is:
   // http://mxr.mozilla.org/firefox/source/modules/plugin/base/src/nsPluginsDirUnix.cpp
diff --git a/webkit/plugins/npapi/plugin_lib_win.cc b/webkit/plugins/npapi/plugin_lib_win.cc
index 224e1c31ce3221..8a0f6cc16f4fba 100644
--- a/webkit/plugins/npapi/plugin_lib_win.cc
+++ b/webkit/plugins/npapi/plugin_lib_win.cc
@@ -15,7 +15,7 @@
 namespace webkit {
 namespace npapi {
 
-bool PluginLib::ReadWebPluginInfo(const FilePath &filename,
+bool PluginLib::ReadWebPluginInfo(const base::FilePath &filename,
                                   WebPluginInfo* info) {
   // On windows, the way we get the mime types for the library is
   // to check the version information in the DLL itself.  This
diff --git a/webkit/plugins/npapi/plugin_list.cc b/webkit/plugins/npapi/plugin_list.cc
index 5bcc9600316fbe..7047a7f0a05f43 100644
--- a/webkit/plugins/npapi/plugin_list.cc
+++ b/webkit/plugins/npapi/plugin_list.cc
@@ -86,7 +86,7 @@ void PluginList::RefreshPlugins() {
   loading_state_ = LOADING_STATE_NEEDS_REFRESH;
 }
 
-void PluginList::AddExtraPluginPath(const FilePath& plugin_path) {
+void PluginList::AddExtraPluginPath(const base::FilePath& plugin_path) {
   if (!NPAPIPluginsSupported()) {
     // TODO(jam): remove and just have CHECK once we're sure this doesn't get
     // triggered.
@@ -101,16 +101,16 @@ void PluginList::AddExtraPluginPath(const FilePath& plugin_path) {
 #endif
 }
 
-void PluginList::RemoveExtraPluginPath(const FilePath& plugin_path) {
+void PluginList::RemoveExtraPluginPath(const base::FilePath& plugin_path) {
   base::AutoLock lock(lock_);
-  std::vector<FilePath>::iterator it =
+  std::vector<base::FilePath>::iterator it =
       std::find(extra_plugin_paths_.begin(), extra_plugin_paths_.end(),
                 plugin_path);
   if (it != extra_plugin_paths_.end())
     extra_plugin_paths_.erase(it);
 }
 
-void PluginList::AddExtraPluginDir(const FilePath& plugin_dir) {
+void PluginList::AddExtraPluginDir(const base::FilePath& plugin_dir) {
   // Chrome OS only loads plugins from /opt/google/chrome/plugins.
 #if !defined(OS_CHROMEOS)
   base::AutoLock lock(lock_);
@@ -148,7 +148,7 @@ void PluginList::RegisterInternalPluginWithEntryPoints(
   }
 }
 
-void PluginList::UnregisterInternalPlugin(const FilePath& path) {
+void PluginList::UnregisterInternalPlugin(const base::FilePath& path) {
   base::AutoLock lock(lock_);
   for (size_t i = 0; i < internal_plugins_.size(); i++) {
     if (internal_plugins_[i].info.path == path) {
@@ -170,7 +170,7 @@ void PluginList::GetInternalPlugins(
   }
 }
 
-bool PluginList::ReadPluginInfo(const FilePath& filename,
+bool PluginList::ReadPluginInfo(const base::FilePath& filename,
                                 webkit::WebPluginInfo* info,
                                 const PluginEntryPoints** entry_points) {
   {
@@ -252,10 +252,10 @@ void PluginList::LoadPluginsIntoPluginListInternal(
   if (!will_load_callback.is_null())
     will_load_callback.Run();
 
-  std::vector<FilePath> plugin_paths;
+  std::vector<base::FilePath> plugin_paths;
   GetPluginPathsToLoad(&plugin_paths);
 
-  for (std::vector<FilePath>::const_iterator it = plugin_paths.begin();
+  for (std::vector<base::FilePath>::const_iterator it = plugin_paths.begin();
        it != plugin_paths.end();
        ++it) {
     WebPluginInfo plugin_info;
@@ -286,7 +286,7 @@ void PluginList::LoadPlugins() {
 }
 
 bool PluginList::LoadPluginIntoPluginList(
-    const FilePath& path,
+    const base::FilePath& path,
     std::vector<webkit::WebPluginInfo>* plugins,
     WebPluginInfo* plugin_info) {
   LOG_IF(ERROR, PluginList::DebugPluginLoading())
@@ -316,11 +316,11 @@ bool PluginList::LoadPluginIntoPluginList(
   return true;
 }
 
-void PluginList::GetPluginPathsToLoad(std::vector<FilePath>* plugin_paths) {
+void PluginList::GetPluginPathsToLoad(std::vector<base::FilePath>* plugin_paths) {
   // Don't want to hold the lock while loading new plugins, so we don't block
   // other methods if they're called on other threads.
-  std::vector<FilePath> extra_plugin_paths;
-  std::vector<FilePath> extra_plugin_dirs;
+  std::vector<base::FilePath> extra_plugin_paths;
+  std::vector<base::FilePath> extra_plugin_dirs;
   {
     base::AutoLock lock(lock_);
     extra_plugin_paths = extra_plugin_paths_;
@@ -328,7 +328,7 @@ void PluginList::GetPluginPathsToLoad(std::vector<FilePath>* plugin_paths) {
   }
 
   for (size_t i = 0; i < extra_plugin_paths.size(); ++i) {
-    const FilePath& path = extra_plugin_paths[i];
+    const base::FilePath& path = extra_plugin_paths[i];
     if (std::find(plugin_paths->begin(), plugin_paths->end(), path) !=
         plugin_paths->end()) {
       continue;
@@ -342,7 +342,7 @@ void PluginList::GetPluginPathsToLoad(std::vector<FilePath>* plugin_paths) {
     for (size_t i = 0; i < extra_plugin_dirs.size(); ++i)
       GetPluginsInDir(extra_plugin_dirs[i], plugin_paths);
 
-    std::vector<FilePath> directories_to_scan;
+    std::vector<base::FilePath> directories_to_scan;
     GetPluginDirectories(&directories_to_scan);
     for (size_t i = 0; i < directories_to_scan.size(); ++i)
       GetPluginsInDir(directories_to_scan[i], plugin_paths);
@@ -401,12 +401,12 @@ void PluginList::GetPluginInfoArray(
   if (actual_mime_types)
     actual_mime_types->clear();
 
-  std::set<FilePath> visited_plugins;
+  std::set<base::FilePath> visited_plugins;
 
   // Add in plugins by mime type.
   for (size_t i = 0; i < plugins_list_.size(); ++i) {
     if (SupportsType(plugins_list_[i], mime_type, allow_wildcard)) {
-      FilePath path = plugins_list_[i].path;
+      base::FilePath path = plugins_list_[i].path;
       if (visited_plugins.insert(path).second) {
         info->push_back(plugins_list_[i]);
         if (actual_mime_types)
@@ -423,7 +423,7 @@ void PluginList::GetPluginInfoArray(
     std::string actual_mime_type;
     for (size_t i = 0; i < plugins_list_.size(); ++i) {
       if (SupportsExtension(plugins_list_[i], extension, &actual_mime_type)) {
-        FilePath path = plugins_list_[i].path;
+        base::FilePath path = plugins_list_[i].path;
         if (visited_plugins.insert(path).second &&
             AllowMimeTypeMismatch(mime_type, actual_mime_type)) {
           info->push_back(plugins_list_[i]);
diff --git a/webkit/plugins/npapi/plugin_list.h b/webkit/plugins/npapi/plugin_list.h
index f34a18a73c9af3..1cd82ed9f4bb18 100644
--- a/webkit/plugins/npapi/plugin_list.h
+++ b/webkit/plugins/npapi/plugin_list.h
@@ -71,14 +71,14 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
 
   // Add/Remove an extra plugin to load when we actually do the loading.  Must
   // be called before the plugins have been loaded.
-  void AddExtraPluginPath(const FilePath& plugin_path);
-  void RemoveExtraPluginPath(const FilePath& plugin_path);
+  void AddExtraPluginPath(const base::FilePath& plugin_path);
+  void RemoveExtraPluginPath(const base::FilePath& plugin_path);
 
   // Same as above, but specifies a directory in which to search for plugins.
-  void AddExtraPluginDir(const FilePath& plugin_dir);
+  void AddExtraPluginDir(const base::FilePath& plugin_dir);
 
   // Get the ordered list of directories from which to load plugins
-  void GetPluginDirectories(std::vector<FilePath>* plugin_dirs);
+  void GetPluginDirectories(std::vector<base::FilePath>* plugin_dirs);
 
   // Register an internal plugin with the specified plugin information.
   // An internal plugin must be registered before it can
@@ -100,7 +100,7 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
   // on the path from the version info previously registered.
   //
   // This is generally only necessary for tests.
-  void UnregisterInternalPlugin(const FilePath& path);
+  void UnregisterInternalPlugin(const base::FilePath& path);
 
   // Gets a list of all the registered internal plugins.
   void GetInternalPlugins(std::vector<webkit::WebPluginInfo>* plugins);
@@ -110,7 +110,7 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
   // internal plugin, "entry_points" is filled in as well with a
   // internally-owned PluginEntryPoints pointer.
   // Returns false if the library couldn't be found, or if it's not a plugin.
-  bool ReadPluginInfo(const FilePath& filename,
+  bool ReadPluginInfo(const base::FilePath& filename,
                       webkit::WebPluginInfo* info,
                       const PluginEntryPoints** entry_points);
 
@@ -153,7 +153,7 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
 
   // Load a specific plugin with full path. Return true iff loading the plug-in
   // was successful.
-  bool LoadPluginIntoPluginList(const FilePath& filename,
+  bool LoadPluginIntoPluginList(const base::FilePath& filename,
                                 std::vector<webkit::WebPluginInfo>* plugins,
                                 webkit::WebPluginInfo* plugin_info);
 
@@ -161,7 +161,7 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
   // using a different instance of this class.
 
   // Computes a list of all plugins to potentially load from all sources.
-  void GetPluginPathsToLoad(std::vector<FilePath>* plugin_paths);
+  void GetPluginPathsToLoad(std::vector<base::FilePath>* plugin_paths);
 
   // Clears the internal list of Plugins and copies them from the vector.
   void SetPlugins(const std::vector<webkit::WebPluginInfo>& plugins);
@@ -200,7 +200,8 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
 
   // Walks a directory and produces a list of all the plugins to potentially
   // load in that directory.
-  void GetPluginsInDir(const FilePath& path, std::vector<FilePath>* plugins);
+  void GetPluginsInDir(const base::FilePath& path,
+                       std::vector<base::FilePath>* plugins);
 
   // Returns true if we should load the given plugin, or false otherwise.
   // |plugins| is the list of plugins we have crawled in the current plugin
@@ -234,7 +235,7 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
 
   // Gets plugin paths registered under HKCU\Software\MozillaPlugins and
   // HKLM\Software\MozillaPlugins.
-  void GetPluginPathsFromRegistry(std::vector<FilePath>* plugins);
+  void GetPluginPathsFromRegistry(std::vector<base::FilePath>* plugins);
 #endif
 
   //
@@ -247,10 +248,10 @@ class WEBKIT_PLUGINS_EXPORT PluginList {
   LoadingState loading_state_;
 
   // Extra plugin paths that we want to search when loading.
-  std::vector<FilePath> extra_plugin_paths_;
+  std::vector<base::FilePath> extra_plugin_paths_;
 
   // Extra plugin directories that we want to search when loading.
-  std::vector<FilePath> extra_plugin_dirs_;
+  std::vector<base::FilePath> extra_plugin_dirs_;
 
   // Holds information about internal plugins.
   std::vector<InternalPlugin> internal_plugins_;
diff --git a/webkit/plugins/npapi/plugin_list_mac.mm b/webkit/plugins/npapi/plugin_list_mac.mm
index 719301d0ece4be..b818f89830187d 100644
--- a/webkit/plugins/npapi/plugin_list_mac.mm
+++ b/webkit/plugins/npapi/plugin_list_mac.mm
@@ -19,7 +19,7 @@
 
 namespace {
 
-void GetPluginCommonDirectory(std::vector<FilePath>* plugin_dirs,
+void GetPluginCommonDirectory(std::vector<base::FilePath>* plugin_dirs,
                               bool user) {
   // Note that there are no NSSearchPathDirectory constants for these
   // directories so we can't use Cocoa's NSSearchPathForDirectoriesInDomains().
@@ -32,7 +32,7 @@ void GetPluginCommonDirectory(std::vector<FilePath>* plugin_dirs,
   if (err)
     return;
 
-  plugin_dirs->push_back(FilePath(base::mac::PathFromFSRef(ref)));
+  plugin_dirs->push_back(base::FilePath(base::mac::PathFromFSRef(ref)));
 }
 
 // Returns true if the plugin should be prevented from loading.
@@ -68,7 +68,7 @@ bool IsBlacklistedPlugin(const WebPluginInfo& info) {
 void PluginList::PlatformInit() {
 }
 
-void PluginList::GetPluginDirectories(std::vector<FilePath>* plugin_dirs) {
+void PluginList::GetPluginDirectories(std::vector<base::FilePath>* plugin_dirs) {
   // Load from the user's area
   GetPluginCommonDirectory(plugin_dirs, true);
 
@@ -77,11 +77,11 @@ bool IsBlacklistedPlugin(const WebPluginInfo& info) {
 }
 
 void PluginList::GetPluginsInDir(
-    const FilePath& path, std::vector<FilePath>* plugins) {
+    const base::FilePath& path, std::vector<base::FilePath>* plugins) {
   file_util::FileEnumerator enumerator(path,
                                        false, // not recursive
                                        file_util::FileEnumerator::DIRECTORIES);
-  for (FilePath path = enumerator.Next(); !path.value().empty();
+  for (base::FilePath path = enumerator.Next(); !path.value().empty();
        path = enumerator.Next()) {
     plugins->push_back(path);
   }
diff --git a/webkit/plugins/npapi/plugin_list_posix.cc b/webkit/plugins/npapi/plugin_list_posix.cc
index 94974a5c9d3480..62c49909a98153 100644
--- a/webkit/plugins/npapi/plugin_list_posix.cc
+++ b/webkit/plugins/npapi/plugin_list_posix.cc
@@ -21,7 +21,7 @@ namespace npapi {
 namespace {
 
 // We build up a list of files and mtimes so we can sort them.
-typedef std::pair<FilePath, base::Time> FileAndTime;
+typedef std::pair<base::FilePath, base::Time> FileAndTime;
 typedef std::vector<FileAndTime> FileTimeList;
 
 enum PluginQuirk {
@@ -63,7 +63,7 @@ bool CheckQuirks(PluginQuirk quirks) {
 // Also check against any PluginQuirks the bad plugin may have.
 // The use of the file size is an optimization so we don't have to read in
 // the entire file unless we have to.
-bool IsBlacklistedBySha1sumAndQuirks(const FilePath& path) {
+bool IsBlacklistedBySha1sumAndQuirks(const base::FilePath& path) {
   const struct BadEntry {
     int64 size;
     std::string sha1;
@@ -123,7 +123,7 @@ bool IsUndesirablePlugin(const WebPluginInfo& info) {
 // This is an ugly hack to blacklist Adobe Acrobat due to not supporting
 // its Xt-based mainloop.
 // http://code.google.com/p/chromium/issues/detail?id=38229
-bool IsBlacklistedPlugin(const FilePath& path) {
+bool IsBlacklistedPlugin(const base::FilePath& path) {
   const char* kBlackListedPlugins[] = {
     "nppdf.so",           // Adobe PDF
   };
@@ -141,7 +141,7 @@ bool IsBlacklistedPlugin(const FilePath& path) {
 void PluginList::PlatformInit() {
 }
 
-void PluginList::GetPluginDirectories(std::vector<FilePath>* plugin_dirs) {
+void PluginList::GetPluginDirectories(std::vector<base::FilePath>* plugin_dirs) {
   // See http://groups.google.com/group/chromium-dev/browse_thread/thread/7a70e5fcbac786a9
   // for discussion.
   // We first consult Chrome-specific dirs, then fall back on the logic
@@ -152,7 +152,7 @@ void PluginList::GetPluginDirectories(std::vector<FilePath>* plugin_dirs) {
   // related to extra_plugin_dirs in plugin_list.cc.
 
   // The Chrome binary dir + "plugins/".
-  FilePath dir;
+  base::FilePath dir;
   PathService::Get(base::DIR_EXE, &dir);
   plugin_dirs->push_back(dir.Append("plugins"));
 
@@ -169,36 +169,36 @@ void PluginList::GetPluginDirectories(std::vector<FilePath>* plugin_dirs) {
     std::vector<std::string> paths;
     base::SplitString(moz_plugin_path, ':', &paths);
     for (size_t i = 0; i < paths.size(); ++i)
-      plugin_dirs->push_back(FilePath(paths[i]));
+      plugin_dirs->push_back(base::FilePath(paths[i]));
   }
 
   // 2) NS_USER_PLUGINS_DIR: ~/.mozilla/plugins.
   // This is a de-facto standard, so even though we're not Mozilla, let's
   // look in there too.
-  FilePath home = file_util::GetHomeDir();
+  base::FilePath home = file_util::GetHomeDir();
   if (!home.empty())
     plugin_dirs->push_back(home.Append(".mozilla/plugins"));
 
   // 3) NS_SYSTEM_PLUGINS_DIR:
   // This varies across different browsers and versions, so check 'em all.
-  plugin_dirs->push_back(FilePath("/usr/lib/browser-plugins"));
-  plugin_dirs->push_back(FilePath("/usr/lib/mozilla/plugins"));
-  plugin_dirs->push_back(FilePath("/usr/lib/firefox/plugins"));
-  plugin_dirs->push_back(FilePath("/usr/lib/xulrunner-addons/plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib/browser-plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib/mozilla/plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib/firefox/plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib/xulrunner-addons/plugins"));
 
 #if defined(ARCH_CPU_64_BITS)
   // On my Ubuntu system, /usr/lib64 is a symlink to /usr/lib.
   // But a user reported on their Fedora system they are separate.
-  plugin_dirs->push_back(FilePath("/usr/lib64/browser-plugins"));
-  plugin_dirs->push_back(FilePath("/usr/lib64/mozilla/plugins"));
-  plugin_dirs->push_back(FilePath("/usr/lib64/firefox/plugins"));
-  plugin_dirs->push_back(FilePath("/usr/lib64/xulrunner-addons/plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib64/browser-plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib64/mozilla/plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib64/firefox/plugins"));
+  plugin_dirs->push_back(base::FilePath("/usr/lib64/xulrunner-addons/plugins"));
 #endif  // defined(ARCH_CPU_64_BITS)
 #endif  // !defined(OS_CHROMEOS)
 }
 
 void PluginList::GetPluginsInDir(
-    const FilePath& dir_path, std::vector<FilePath>* plugins) {
+    const base::FilePath& dir_path, std::vector<base::FilePath>* plugins) {
   // See ScanPluginsDirectory near
   // http://mxr.mozilla.org/firefox/source/modules/plugin/base/src/nsPluginHostImpl.cpp#5052
 
@@ -208,7 +208,7 @@ void PluginList::GetPluginsInDir(
   file_util::FileEnumerator enumerator(dir_path,
                                        false,  // not recursive
                                        file_util::FileEnumerator::FILES);
-  for (FilePath path = enumerator.Next(); !path.value().empty();
+  for (base::FilePath path = enumerator.Next(); !path.value().empty();
        path = enumerator.Next()) {
     // Skip over Mozilla .xpt files.
     if (path.MatchesExtension(FILE_PATH_LITERAL(".xpt")))
@@ -218,7 +218,7 @@ void PluginList::GetPluginsInDir(
     // its path to find dependent data files.
     // file_util::AbsolutePath calls through to realpath(), which resolves
     // symlinks.
-    FilePath orig_path = path;
+    base::FilePath orig_path = path;
     file_util::AbsolutePath(&path);
     LOG_IF(ERROR, PluginList::DebugPluginLoading())
         << "Resolved " << orig_path.value() << " -> " << path.value();
diff --git a/webkit/plugins/npapi/plugin_list_unittest.cc b/webkit/plugins/npapi/plugin_list_unittest.cc
index 5d198d129808f4..0fc55bf80c21ea 100644
--- a/webkit/plugins/npapi/plugin_list_unittest.cc
+++ b/webkit/plugins/npapi/plugin_list_unittest.cc
@@ -31,8 +31,8 @@ bool Contains(const std::vector<WebPluginInfo>& list,
   return false;
 }
 
-FilePath::CharType kFooPath[] = FILE_PATH_LITERAL("/plugins/foo.plugin");
-FilePath::CharType kBarPath[] = FILE_PATH_LITERAL("/plugins/bar.plugin");
+base::FilePath::CharType kFooPath[] = FILE_PATH_LITERAL("/plugins/foo.plugin");
+base::FilePath::CharType kBarPath[] = FILE_PATH_LITERAL("/plugins/bar.plugin");
 const char* kFooName = "Foo Plugin";
 
 }  // namespace
@@ -41,11 +41,11 @@ class PluginListTest : public testing::Test {
  public:
   PluginListTest()
       : foo_plugin_(ASCIIToUTF16(kFooName),
-                    FilePath(kFooPath),
+                    base::FilePath(kFooPath),
                     ASCIIToUTF16("1.2.3"),
                     ASCIIToUTF16("foo")),
         bar_plugin_(ASCIIToUTF16("Bar Plugin"),
-                    FilePath(kBarPath),
+                    base::FilePath(kBarPath),
                     ASCIIToUTF16("2.3.4"),
                     ASCIIToUTF16("bar")) {
   }
@@ -71,7 +71,7 @@ TEST_F(PluginListTest, GetPlugins) {
 
 TEST_F(PluginListTest, BadPluginDescription) {
   WebPluginInfo plugin_3043(
-      string16(), FilePath(FILE_PATH_LITERAL("/myplugin.3.0.43")),
+      string16(), base::FilePath(FILE_PATH_LITERAL("/myplugin.3.0.43")),
       string16(), string16());
   // Simulate loading of the plugins.
   plugin_list_.ClearPluginsToLoad();
diff --git a/webkit/plugins/npapi/plugin_list_win.cc b/webkit/plugins/npapi/plugin_list_win.cc
index 22dce6389cedb8..0f19d08d7e1e24 100644
--- a/webkit/plugins/npapi/plugin_list_win.cc
+++ b/webkit/plugins/npapi/plugin_list_win.cc
@@ -43,7 +43,7 @@ const char16 kRegistryJavaHome[] = L"JavaHome";
 const char16 kJavaDeploy1[] = L"npdeploytk.dll";
 const char16 kJavaDeploy2[] = L"npdeployjava1.dll";
 
-FilePath AppendPluginsDir(const FilePath& path) {
+base::FilePath AppendPluginsDir(const base::FilePath& path) {
   return path.AppendASCII("plugins");
 }
 
@@ -51,8 +51,8 @@ FilePath AppendPluginsDir(const FilePath& path) {
 // may be a versioned subdirectory, or it may be the same directory as the
 // GetExeDirectory(), depending on the embedder's implementation.
 // Path is an output parameter to receive the path.
-void GetAppDirectory(std::set<FilePath>* plugin_dirs) {
-  FilePath app_path;
+void GetAppDirectory(std::set<base::FilePath>* plugin_dirs) {
+  base::FilePath app_path;
   if (!PathService::Get(base::DIR_MODULE, &app_path))
     return;
   plugin_dirs->insert(AppendPluginsDir(app_path));
@@ -60,15 +60,15 @@ void GetAppDirectory(std::set<FilePath>* plugin_dirs) {
 
 // Gets the directory where the launching executable resides on disk.
 // Path is an output parameter to receive the path.
-void GetExeDirectory(std::set<FilePath>* plugin_dirs) {
-  FilePath exe_path;
+void GetExeDirectory(std::set<base::FilePath>* plugin_dirs) {
+  base::FilePath exe_path;
   if (!PathService::Get(base::DIR_EXE, &exe_path))
     return;
   plugin_dirs->insert(AppendPluginsDir(exe_path));
 }
 
 // Gets the installed path for a registered app.
-bool GetInstalledPath(const char16* app, FilePath* out) {
+bool GetInstalledPath(const char16* app, base::FilePath* out) {
   string16 reg_path(kRegistryApps);
   reg_path.append(L"\\");
   reg_path.append(app);
@@ -78,12 +78,12 @@ bool GetInstalledPath(const char16* app, FilePath* out) {
   // As of Win7 AppPaths can also be registered in HKCU: http://goo.gl/UgFOf.
   if (base::win::GetVersion() >= base::win::VERSION_WIN7 &&
       hkcu_key.ReadValue(kRegistryPath, &path) == ERROR_SUCCESS) {
-    *out = FilePath(path);
+    *out = base::FilePath(path);
     return true;
   } else {
     base::win::RegKey hklm_key(HKEY_LOCAL_MACHINE, reg_path.c_str(), KEY_READ);
     if (hklm_key.ReadValue(kRegistryPath, &path) == ERROR_SUCCESS) {
-      *out = FilePath(path);
+      *out = base::FilePath(path);
       return true;
     }
   }
@@ -95,7 +95,7 @@ bool GetInstalledPath(const char16* app, FilePath* out) {
 void GetPluginsInRegistryDirectory(
     HKEY root_key,
     const string16& registry_folder,
-    std::set<FilePath>* plugin_dirs) {
+    std::set<base::FilePath>* plugin_dirs) {
   for (base::win::RegistryKeyIterator iter(root_key, registry_folder.c_str());
        iter.Valid(); ++iter) {
     // Use the registry to gather plugin across the file system.
@@ -106,13 +106,13 @@ void GetPluginsInRegistryDirectory(
 
     string16 path;
     if (key.ReadValue(kRegistryPath, &path) == ERROR_SUCCESS)
-      plugin_dirs->insert(FilePath(path));
+      plugin_dirs->insert(base::FilePath(path));
   }
 }
 
 // Enumerate through the registry key to find all installed FireFox paths.
 // FireFox 3 beta and version 2 can coexist. See bug: 1025003
-void GetFirefoxInstalledPaths(std::vector<FilePath>* out) {
+void GetFirefoxInstalledPaths(std::vector<base::FilePath>* out) {
   base::win::RegistryKeyIterator it(HKEY_LOCAL_MACHINE,
                                     kRegistryFirefoxInstalled);
   for (; it.Valid(); ++it) {
@@ -122,7 +122,7 @@ void GetFirefoxInstalledPaths(std::vector<FilePath>* out) {
     string16 install_dir;
     if (key.ReadValue(L"Install Directory", &install_dir) != ERROR_SUCCESS)
       continue;
-    out->push_back(FilePath(install_dir));
+    out->push_back(base::FilePath(install_dir));
   }
 }
 
@@ -130,14 +130,14 @@ void GetFirefoxInstalledPaths(std::vector<FilePath>* out) {
 // of a kludge, but it helps us locate the flash player for users that
 // already have it for firefox.  Not having to download yet-another-plugin
 // is a good thing.
-void GetFirefoxDirectory(std::set<FilePath>* plugin_dirs) {
-  std::vector<FilePath> paths;
+void GetFirefoxDirectory(std::set<base::FilePath>* plugin_dirs) {
+  std::vector<base::FilePath> paths;
   GetFirefoxInstalledPaths(&paths);
   for (unsigned int i = 0; i < paths.size(); ++i) {
     plugin_dirs->insert(AppendPluginsDir(paths[i]));
   }
 
-  FilePath firefox_app_data_plugin_path;
+  base::FilePath firefox_app_data_plugin_path;
   if (PathService::Get(base::DIR_APP_DATA, &firefox_app_data_plugin_path)) {
     firefox_app_data_plugin_path =
         firefox_app_data_plugin_path.AppendASCII("Mozilla");
@@ -146,8 +146,8 @@ void GetFirefoxDirectory(std::set<FilePath>* plugin_dirs) {
 }
 
 // Hardcoded logic to detect Acrobat plugins locations.
-void GetAcrobatDirectory(std::set<FilePath>* plugin_dirs) {
-  FilePath path;
+void GetAcrobatDirectory(std::set<base::FilePath>* plugin_dirs) {
+  base::FilePath path;
   if (!GetInstalledPath(kRegistryAcrobatReader, &path) &&
       !GetInstalledPath(kRegistryAcrobat, &path)) {
     return;
@@ -157,21 +157,21 @@ void GetAcrobatDirectory(std::set<FilePath>* plugin_dirs) {
 }
 
 // Hardcoded logic to detect QuickTime plugin location.
-void GetQuicktimeDirectory(std::set<FilePath>* plugin_dirs) {
-  FilePath path;
+void GetQuicktimeDirectory(std::set<base::FilePath>* plugin_dirs) {
+  base::FilePath path;
   if (GetInstalledPath(kRegistryQuickTime, &path))
     plugin_dirs->insert(AppendPluginsDir(path));
 }
 
 // Hardcoded logic to detect Windows Media Player plugin location.
-void GetWindowsMediaDirectory(std::set<FilePath>* plugin_dirs) {
-  FilePath path;
+void GetWindowsMediaDirectory(std::set<base::FilePath>* plugin_dirs) {
+  base::FilePath path;
   if (GetInstalledPath(kRegistryWindowsMedia, &path))
     plugin_dirs->insert(path);
 }
 
 // Hardcoded logic to detect Java plugin location.
-void GetJavaDirectory(std::set<FilePath>* plugin_dirs) {
+void GetJavaDirectory(std::set<base::FilePath>* plugin_dirs) {
   // Load the new NPAPI Java plugin
   // 1. Open the main JRE key under HKLM
   base::win::RegKey java_key(HKEY_LOCAL_MACHINE, kRegistryJava,
@@ -199,12 +199,12 @@ void GetJavaDirectory(std::set<FilePath>* plugin_dirs) {
 
       // 5. We don't know the exact name of the DLL but it's in the form
       //    NP*.dll so just invoke LoadPlugins on this path.
-      plugin_dirs->insert(FilePath(java_plugin_directory));
+      plugin_dirs->insert(base::FilePath(java_plugin_directory));
     }
   }
 }
 
-bool IsValid32BitImage(const FilePath& path) {
+bool IsValid32BitImage(const base::FilePath& path) {
   file_util::MemoryMappedFile plugin_image;
 
   if (!plugin_image.InitializeAsImageSection(path))
@@ -266,9 +266,9 @@ void PluginList::PlatformInit() {
   dont_load_new_wmp_ = command_line.HasSwitch(switches::kUseOldWMPPlugin);
 }
 
-void PluginList::GetPluginDirectories(std::vector<FilePath>* plugin_dirs) {
+void PluginList::GetPluginDirectories(std::vector<base::FilePath>* plugin_dirs) {
   // We use a set for uniqueness, which we require, over order, which we do not.
-  std::set<FilePath> dirs;
+  std::set<base::FilePath> dirs;
 
   // Load from the application-specific area
   GetAppDirectory(&dirs);
@@ -289,12 +289,12 @@ void PluginList::GetPluginDirectories(std::vector<FilePath>* plugin_dirs) {
   GetQuicktimeDirectory(&dirs);
   GetWindowsMediaDirectory(&dirs);
 
-  for (std::set<FilePath>::iterator i = dirs.begin(); i != dirs.end(); ++i)
+  for (std::set<base::FilePath>::iterator i = dirs.begin(); i != dirs.end(); ++i)
     plugin_dirs->push_back(*i);
 }
 
 void PluginList::GetPluginsInDir(
-    const FilePath& path, std::vector<FilePath>* plugins) {
+    const base::FilePath& path, std::vector<base::FilePath>* plugins) {
   WIN32_FIND_DATA find_file_data;
   HANDLE find_handle;
 
@@ -308,7 +308,7 @@ void PluginList::GetPluginsInDir(
 
   do {
     if (!(find_file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) {
-      FilePath filename = path.Append(find_file_data.cFileName);
+      base::FilePath filename = path.Append(find_file_data.cFileName);
       plugins->push_back(filename);
     }
   } while (FindNextFile(find_handle, &find_file_data) != 0);
@@ -317,15 +317,15 @@ void PluginList::GetPluginsInDir(
   FindClose(find_handle);
 }
 
-void PluginList::GetPluginPathsFromRegistry(std::vector<FilePath>* plugins) {
-  std::set<FilePath> plugin_dirs;
+void PluginList::GetPluginPathsFromRegistry(std::vector<base::FilePath>* plugins) {
+  std::set<base::FilePath> plugin_dirs;
 
   GetPluginsInRegistryDirectory(
       HKEY_CURRENT_USER, kRegistryMozillaPlugins, &plugin_dirs);
   GetPluginsInRegistryDirectory(
       HKEY_LOCAL_MACHINE, kRegistryMozillaPlugins, &plugin_dirs);
 
-  for (std::set<FilePath>::iterator i = plugin_dirs.begin();
+  for (std::set<base::FilePath>::iterator i = plugin_dirs.begin();
        i != plugin_dirs.end(); ++i) {
     plugins->push_back(*i);
   }
@@ -336,9 +336,9 @@ bool PluginList::ShouldLoadPluginUsingPluginList(
     std::vector<webkit::WebPluginInfo>* plugins) {
   // Version check
   for (size_t j = 0; j < plugins->size(); ++j) {
-    FilePath::StringType plugin1 =
+    base::FilePath::StringType plugin1 =
         StringToLowerASCII((*plugins)[j].path.BaseName().value());
-    FilePath::StringType plugin2 =
+    base::FilePath::StringType plugin2 =
         StringToLowerASCII(info.path.BaseName().value());
     if ((plugin1 == plugin2 && HaveSharedMimeType((*plugins)[j], info)) ||
         (plugin1 == kJavaDeploy1 && plugin2 == kJavaDeploy2) ||
@@ -361,7 +361,7 @@ bool PluginList::ShouldLoadPluginUsingPluginList(
   }
 
   // Troublemakers.
-  FilePath::StringType filename =
+  base::FilePath::StringType filename =
       StringToLowerASCII(info.path.BaseName().value());
   // Depends on XPCOM.
   if (filename == kMozillaActiveXPlugin)
@@ -383,7 +383,7 @@ bool PluginList::ShouldLoadPluginUsingPluginList(
   // We only work with newer versions of the Java plugin which use NPAPI only
   // and don't depend on XPCOM.
   if (filename == kJavaPlugin1 || filename == kJavaPlugin2) {
-    std::vector<FilePath::StringType> ver;
+    std::vector<base::FilePath::StringType> ver;
     base::SplitString(info.version, '.', &ver);
     int major, minor, update;
     if (ver.size() == 4 &&
@@ -417,7 +417,7 @@ bool PluginList::ShouldLoadPluginUsingPluginList(
 
 #if !defined(ARCH_CPU_X86_64)
   // The plugin in question could be a 64 bit plugin which we cannot load.
-  FilePath plugin_path(info.path);
+  base::FilePath plugin_path(info.path);
   file_util::AbsolutePath(&plugin_path);
   if (!IsValid32BitImage(plugin_path))
     return false;
diff --git a/webkit/plugins/npapi/plugin_stream.cc b/webkit/plugins/npapi/plugin_stream.cc
index 894603014c1d09..543ab3efd296cf 100644
--- a/webkit/plugins/npapi/plugin_stream.cc
+++ b/webkit/plugins/npapi/plugin_stream.cc
@@ -84,9 +84,9 @@ bool PluginStream::Open(const std::string& mime_type,
     GURL gurl(stream_.url);
 
 #if defined(OS_WIN)
-    FilePath path(UTF8ToWide(gurl.path()));
+    base::FilePath path(UTF8ToWide(gurl.path()));
 #elif defined(OS_POSIX)
-    FilePath path(gurl.path());
+    base::FilePath path(gurl.path());
 #endif
     if (net::GetMimeTypeFromFile(path, &temp_mime_type))
       char_mime_type = temp_mime_type.c_str();
diff --git a/webkit/plugins/npapi/plugin_stream.h b/webkit/plugins/npapi/plugin_stream.h
index 2bc691af698c51..10993f03e74138 100644
--- a/webkit/plugins/npapi/plugin_stream.h
+++ b/webkit/plugins/npapi/plugin_stream.h
@@ -146,7 +146,7 @@ class PluginStream : public base::RefCounted<PluginStream> {
   HANDLE                        temp_file_handle_;
 #elif defined(OS_POSIX)
   FILE*                         temp_file_;
-  FilePath                      temp_file_path_;
+  base::FilePath                temp_file_path_;
 #endif
   std::vector<char>             delivery_data_;
   int                           data_offset_;
diff --git a/webkit/plugins/npapi/plugin_stream_posix.cc b/webkit/plugins/npapi/plugin_stream_posix.cc
index 3422d997eab219..ab4b0d4404fd90 100644
--- a/webkit/plugins/npapi/plugin_stream_posix.cc
+++ b/webkit/plugins/npapi/plugin_stream_posix.cc
@@ -19,7 +19,7 @@ void PluginStream::ResetTempFileHandle() {
 }
 
 void PluginStream::ResetTempFileName() {
-  temp_file_path_ = FilePath();
+  temp_file_path_ = base::FilePath();
 }
 
 void PluginStream::WriteAsFile() {
diff --git a/webkit/plugins/npapi/test/plugin_geturl_test.cc b/webkit/plugins/npapi/test/plugin_geturl_test.cc
index f03c5c31787d4b..b1ab554e498ed5 100644
--- a/webkit/plugins/npapi/test/plugin_geturl_test.cc
+++ b/webkit/plugins/npapi/test/plugin_geturl_test.cc
@@ -187,10 +187,10 @@ NPError PluginGetURLTest::NewStream(NPMIMEType type, NPStream* stream,
 #if defined(OS_WIN)
         filename = filename.substr(8);  // remove "file:///"
         // Assume an ASCII path on Windows.
-        FilePath path = FilePath(ASCIIToWide(filename));
+        base::FilePath path = base::FilePath(ASCIIToWide(filename));
 #else
         filename = filename.substr(7);  // remove "file://"
-        FilePath path = FilePath(filename);
+        base::FilePath path = base::FilePath(filename);
 #endif
 
         test_file_ = file_util::OpenFile(path, "r");
diff --git a/webkit/plugins/npapi/webplugin_delegate_impl.cc b/webkit/plugins/npapi/webplugin_delegate_impl.cc
index e3f5785e335d0d..3ff611632fd1e6 100644
--- a/webkit/plugins/npapi/webplugin_delegate_impl.cc
+++ b/webkit/plugins/npapi/webplugin_delegate_impl.cc
@@ -24,7 +24,7 @@ namespace webkit {
 namespace npapi {
 
 WebPluginDelegateImpl* WebPluginDelegateImpl::Create(
-    const FilePath& filename,
+    const base::FilePath& filename,
     const std::string& mime_type) {
   scoped_refptr<PluginLib> plugin_lib(PluginLib::CreatePluginLib(filename));
   if (plugin_lib.get() == NULL)
@@ -239,7 +239,7 @@ void WebPluginDelegateImpl::DidManualLoadFail() {
   instance()->DidManualLoadFail();
 }
 
-FilePath WebPluginDelegateImpl::GetPluginPath() {
+base::FilePath WebPluginDelegateImpl::GetPluginPath() {
   return instance()->plugin_lib()->plugin_info().path;
 }
 
diff --git a/webkit/plugins/npapi/webplugin_delegate_impl.h b/webkit/plugins/npapi/webplugin_delegate_impl.h
index 38f18cd9e3317c..d0a624b1693efc 100644
--- a/webkit/plugins/npapi/webplugin_delegate_impl.h
+++ b/webkit/plugins/npapi/webplugin_delegate_impl.h
@@ -27,7 +27,9 @@
 typedef struct _GdkDrawable GdkPixmap;
 #endif
 
+namespace base {
 class FilePath;
+}
 
 #if defined(OS_MACOSX)
 #ifdef __OBJC__
@@ -77,7 +79,7 @@ class WEBKIT_PLUGINS_EXPORT WebPluginDelegateImpl : public WebPluginDelegate {
     PLUGIN_QUIRK_EMULATE_IME = 131072,  // Windows.
   };
 
-  static WebPluginDelegateImpl* Create(const FilePath& filename,
+  static WebPluginDelegateImpl* Create(const base::FilePath& filename,
                                        const std::string& mime_type);
 
 #if defined(OS_WIN)
@@ -138,7 +140,7 @@ class WEBKIT_PLUGINS_EXPORT WebPluginDelegateImpl : public WebPluginDelegate {
   gfx::Rect GetClipRect() const { return clip_rect_; }
 
   // Returns the path for the library implementing this plugin.
-  FilePath GetPluginPath();
+  base::FilePath GetPluginPath();
 
   // Returns a combination of PluginQuirks.
   int GetQuirks() const { return quirks_; }
diff --git a/webkit/plugins/npapi/webplugin_impl.cc b/webkit/plugins/npapi/webplugin_impl.cc
index 64a36e2a316624..357bb0145310b6 100644
--- a/webkit/plugins/npapi/webplugin_impl.cc
+++ b/webkit/plugins/npapi/webplugin_impl.cc
@@ -464,7 +464,7 @@ bool WebPluginImpl::isPlaceholder() {
 WebPluginImpl::WebPluginImpl(
     WebFrame* webframe,
     const WebPluginParams& params,
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const base::WeakPtr<WebPluginPageDelegate>& page_delegate)
     : windowless_(false),
       window_(gfx::kNullPluginWindow),
diff --git a/webkit/plugins/npapi/webplugin_impl.h b/webkit/plugins/npapi/webplugin_impl.h
index 844ddd4a66f0e0..90ac2802e714e7 100644
--- a/webkit/plugins/npapi/webplugin_impl.h
+++ b/webkit/plugins/npapi/webplugin_impl.h
@@ -58,7 +58,7 @@ class WEBKIT_PLUGINS_EXPORT WebPluginImpl :
   WebPluginImpl(
       WebKit::WebFrame* frame,
       const WebKit::WebPluginParams& params,
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       const base::WeakPtr<WebPluginPageDelegate>& page_delegate);
   virtual ~WebPluginImpl();
 
@@ -315,7 +315,7 @@ class WEBKIT_PLUGINS_EXPORT WebPluginImpl :
   WebPluginGeometry geometry_;
 
   // The location of the plugin on disk.
-  FilePath file_path_;
+  base::FilePath file_path_;
 
   // The mime type of the plugin.
   std::string mime_type_;
diff --git a/webkit/plugins/npapi/webplugin_page_delegate.h b/webkit/plugins/npapi/webplugin_page_delegate.h
index ec4b34a26cd71b..e632014b4349dc 100644
--- a/webkit/plugins/npapi/webplugin_page_delegate.h
+++ b/webkit/plugins/npapi/webplugin_page_delegate.h
@@ -9,7 +9,9 @@
 
 #include "ui/gfx/native_widget_types.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace WebKit {
 class WebCookieJar;
@@ -29,12 +31,12 @@ class WebPluginPageDelegate {
   // new plugin is instanced.  See CreateWebPluginDelegateHelper
   // for a default WebPluginDelegate implementation.
   virtual WebPluginDelegate* CreatePluginDelegate(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       const std::string& mime_type) = 0;
 
   // Caled to create a replacement plug-in when loading a plug-in failed.
   virtual WebKit::WebPlugin* CreatePluginReplacement(
-      const FilePath& file_path) = 0;
+      const base::FilePath& file_path) = 0;
 
   // Called when a windowed plugin is created.
   // Lets the view delegate create anything it is using to wrap the plugin.
diff --git a/webkit/plugins/ppapi/file_callbacks.cc b/webkit/plugins/ppapi/file_callbacks.cc
index 0ab4453bbb0811..dd8906d28ff8a4 100644
--- a/webkit/plugins/ppapi/file_callbacks.cc
+++ b/webkit/plugins/ppapi/file_callbacks.cc
@@ -46,7 +46,7 @@ void FileCallbacks::DidSucceed() {
 
 void FileCallbacks::DidReadMetadata(
     const base::PlatformFileInfo& file_info,
-    const FilePath& unused) {
+    const base::FilePath& unused) {
   if (callback_->completed())
     return;
 
diff --git a/webkit/plugins/ppapi/file_callbacks.h b/webkit/plugins/ppapi/file_callbacks.h
index c254dab9030b87..2e31e2fd19c91d 100644
--- a/webkit/plugins/ppapi/file_callbacks.h
+++ b/webkit/plugins/ppapi/file_callbacks.h
@@ -46,7 +46,7 @@ class FileCallbacks : public fileapi::FileSystemCallbackDispatcher {
   virtual void DidSucceed();
   virtual void DidReadMetadata(
       const base::PlatformFileInfo& file_info,
-      const FilePath& unused);
+      const base::FilePath& unused);
   virtual void DidReadDirectory(
       const std::vector<base::FileUtilProxy::Entry>& entries, bool has_more);
   virtual void DidOpenFileSystem(const std::string&,
diff --git a/webkit/plugins/ppapi/mock_plugin_delegate.cc b/webkit/plugins/ppapi/mock_plugin_delegate.cc
index d54356a99716bd..e60a6efc0ac961 100644
--- a/webkit/plugins/ppapi/mock_plugin_delegate.cc
+++ b/webkit/plugins/ppapi/mock_plugin_delegate.cc
@@ -68,7 +68,7 @@ SkBitmap* MockPluginDelegate::GetSadPluginBitmap() {
 }
 
 WebKit::WebPlugin* MockPluginDelegate::CreatePluginReplacement(
-    const FilePath& file_path) {
+    const base::FilePath& file_path) {
   return NULL;
 }
 
@@ -141,7 +141,7 @@ void MockPluginDelegate::NumberOfFindResultsChanged(int identifier,
 void MockPluginDelegate::SelectedFindResultChanged(int identifier, int index) {
 }
 
-bool MockPluginDelegate::AsyncOpenFile(const FilePath& path,
+bool MockPluginDelegate::AsyncOpenFile(const base::FilePath& path,
                                        int flags,
                                        const AsyncOpenFileCallback& callback) {
   return false;
@@ -222,9 +222,9 @@ void MockPluginDelegate::DidUpdateFile(const GURL& file_path, int64_t delta) {
 
 void MockPluginDelegate::SyncGetFileSystemPlatformPath(
     const GURL& url,
-    FilePath* platform_path) {
+    base::FilePath* platform_path) {
   DCHECK(platform_path);
-  *platform_path = FilePath();
+  *platform_path = base::FilePath();
 }
 
 scoped_refptr<base::MessageLoopProxy>
diff --git a/webkit/plugins/ppapi/mock_plugin_delegate.h b/webkit/plugins/ppapi/mock_plugin_delegate.h
index de4c28f67336b0..c4c1342f8220c0 100644
--- a/webkit/plugins/ppapi/mock_plugin_delegate.h
+++ b/webkit/plugins/ppapi/mock_plugin_delegate.h
@@ -35,7 +35,8 @@ class MockPluginDelegate : public PluginDelegate {
   virtual scoped_ptr< ::ppapi::thunk::ResourceCreationAPI>
       CreateResourceCreationAPI(PluginInstance* instance);
   virtual SkBitmap* GetSadPluginBitmap();
-  virtual WebKit::WebPlugin* CreatePluginReplacement(const FilePath& file_path);
+  virtual WebKit::WebPlugin* CreatePluginReplacement(
+      const base::FilePath& file_path);
   virtual PlatformImage2D* CreateImage2D(int width, int height);
   virtual PlatformGraphics2D* GetGraphics2D(PluginInstance* instance,
                                             PP_Resource graphics_2d);
@@ -63,7 +64,7 @@ class MockPluginDelegate : public PluginDelegate {
                                           int total,
                                           bool final_result);
   virtual void SelectedFindResultChanged(int identifier, int index);
-  virtual bool AsyncOpenFile(const FilePath& path,
+  virtual bool AsyncOpenFile(const base::FilePath& path,
                              int flags,
                              const AsyncOpenFileCallback& callback);
   virtual bool AsyncOpenFileSystemURL(
@@ -102,7 +103,7 @@ class MockPluginDelegate : public PluginDelegate {
   virtual void WillUpdateFile(const GURL& file_path);
   virtual void DidUpdateFile(const GURL& file_path, int64_t delta);
   virtual void SyncGetFileSystemPlatformPath(const GURL& url,
-                                             FilePath* platform_path);
+                                             base::FilePath* platform_path);
   virtual scoped_refptr<base::MessageLoopProxy>
       GetFileThreadMessageLoopProxy();
   virtual uint32 TCPSocketCreate();
diff --git a/webkit/plugins/ppapi/plugin_delegate.h b/webkit/plugins/ppapi/plugin_delegate.h
index 3f6d05866d2398..5b7b923095b9c8 100644
--- a/webkit/plugins/ppapi/plugin_delegate.h
+++ b/webkit/plugins/ppapi/plugin_delegate.h
@@ -392,7 +392,7 @@ class PluginDelegate {
   // Creates a replacement plug-in that is shown when the plug-in at |file_path|
   // couldn't be loaded.
   virtual WebKit::WebPlugin* CreatePluginReplacement(
-      const FilePath& file_path) = 0;
+      const base::FilePath& file_path) = 0;
 
   // The caller will own the pointer returned from this.
   virtual PlatformImage2D* CreateImage2D(int width, int height) = 0;
@@ -460,7 +460,7 @@ class PluginDelegate {
   // Sends an async IPC to open a local file.
   typedef base::Callback<void (base::PlatformFileError, base::PassPlatformFile)>
       AsyncOpenFileCallback;
-  virtual bool AsyncOpenFile(const FilePath& path,
+  virtual bool AsyncOpenFile(const base::FilePath& path,
                              int flags,
                              const AsyncOpenFileCallback& callback) = 0;
 
@@ -518,7 +518,7 @@ class PluginDelegate {
 
   // Synchronously returns the platform file path for a filesystem URL.
   virtual void SyncGetFileSystemPlatformPath(const GURL& url,
-                                             FilePath* platform_path) = 0;
+                                             base::FilePath* platform_path) = 0;
 
   // Returns a MessageLoopProxy instance associated with the message loop
   // of the file thread in this renderer.
diff --git a/webkit/plugins/ppapi/plugin_module.cc b/webkit/plugins/ppapi/plugin_module.cc
index de17710e721aae..d0218641c0ec57 100644
--- a/webkit/plugins/ppapi/plugin_module.cc
+++ b/webkit/plugins/ppapi/plugin_module.cc
@@ -400,7 +400,7 @@ PluginModule::EntryPoints::EntryPoints()
 // PluginModule ----------------------------------------------------------------
 
 PluginModule::PluginModule(const std::string& name,
-                           const FilePath& path,
+                           const base::FilePath& path,
                            PluginDelegate::ModuleLifetime* lifetime_delegate,
                            const ::ppapi::PpapiPermissions& perms)
     : lifetime_delegate_(lifetime_delegate),
@@ -476,7 +476,7 @@ bool PluginModule::InitAsInternalPlugin(const EntryPoints& entry_points) {
   return false;
 }
 
-bool PluginModule::InitAsLibrary(const FilePath& path) {
+bool PluginModule::InitAsLibrary(const base::FilePath& path) {
   base::NativeLibrary library = base::LoadNativeLibrary(path, NULL);
   if (!library)
     return false;
diff --git a/webkit/plugins/ppapi/plugin_module.h b/webkit/plugins/ppapi/plugin_module.h
index 4d47459fbdfc84..ecf17bbbe75a75 100644
--- a/webkit/plugins/ppapi/plugin_module.h
+++ b/webkit/plugins/ppapi/plugin_module.h
@@ -26,9 +26,12 @@
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 #include "webkit/plugins/webkit_plugins_export.h"
 
-class FilePath;
 typedef void* NPIdentifier;
 
+namespace base {
+class FilePath;
+}
+
 namespace ppapi {
 class CallbackTracker;
 class WebKitForwarding;
@@ -83,7 +86,7 @@ class WEBKIT_PLUGINS_EXPORT PluginModule :
   // all plugin modules. In practice it will be a global singleton that
   // tracks which modules are alive.
   PluginModule(const std::string& name,
-               const FilePath& path,
+               const base::FilePath& path,
                PluginDelegate::ModuleLifetime* lifetime_delegate,
                const ::ppapi::PpapiPermissions& perms);
 
@@ -104,7 +107,7 @@ class WEBKIT_PLUGINS_EXPORT PluginModule :
 
   // Initializes this module using the given library path as the plugin.
   // Returns true on success. False means that the plugin can not be used.
-  bool InitAsLibrary(const FilePath& path);
+  bool InitAsLibrary(const base::FilePath& path);
 
   // Initializes this module for the given out of process proxy. This takes
   // ownership of the given pointer, even in the failure case.
@@ -144,7 +147,7 @@ class WEBKIT_PLUGINS_EXPORT PluginModule :
   PP_Module pp_module() const { return pp_module_; }
 
   const std::string& name() const { return name_; }
-  const FilePath& path() const { return path_; }
+  const base::FilePath& path() const { return path_; }
   const ::ppapi::PpapiPermissions& permissions() const { return permissions_; }
 
   PluginInstance* CreateInstance(PluginDelegate* delegate,
@@ -241,7 +244,7 @@ class WEBKIT_PLUGINS_EXPORT PluginModule :
 
   // The name and file location of the module.
   const std::string name_;
-  const FilePath path_;
+  const base::FilePath path_;
 
   ::ppapi::PpapiPermissions permissions_;
 
diff --git a/webkit/plugins/ppapi/ppapi_unittest.cc b/webkit/plugins/ppapi/ppapi_unittest.cc
index 05dbfed07f1e7c..bccebd933f49cc 100644
--- a/webkit/plugins/ppapi/ppapi_unittest.cc
+++ b/webkit/plugins/ppapi/ppapi_unittest.cc
@@ -78,7 +78,7 @@ void PpapiUnittest::SetUp() {
   delegate_.reset(NewPluginDelegate());
 
   // Initialize the mock module.
-  module_ = new PluginModule("Mock plugin", FilePath(), this,
+  module_ = new PluginModule("Mock plugin", base::FilePath(), this,
                              ::ppapi::PpapiPermissions());
   PluginModule::EntryPoints entry_points;
   entry_points.get_interface = &MockGetInterface;
diff --git a/webkit/plugins/ppapi/ppb_directory_reader_impl.cc b/webkit/plugins/ppapi/ppb_directory_reader_impl.cc
index ec1315ea6161e8..7cd8d5d0e9b2c4 100644
--- a/webkit/plugins/ppapi/ppb_directory_reader_impl.cc
+++ b/webkit/plugins/ppapi/ppb_directory_reader_impl.cc
@@ -33,7 +33,7 @@ namespace ppapi {
 
 namespace {
 
-std::string FilePathStringToUTF8String(const FilePath::StringType& str) {
+std::string FilePathStringToUTF8String(const base::FilePath::StringType& str) {
 #if defined(OS_WIN)
   return WideToUTF8(str);
 #elif defined(OS_POSIX)
@@ -43,7 +43,7 @@ std::string FilePathStringToUTF8String(const FilePath::StringType& str) {
 #endif
 }
 
-FilePath::StringType UTF8StringToFilePathString(const std::string& str) {
+base::FilePath::StringType UTF8StringToFilePathString(const std::string& str) {
 #if defined(OS_WIN)
   return UTF8ToWide(str);
 #elif defined(OS_POSIX)
@@ -110,7 +110,7 @@ void PPB_DirectoryReader_Impl::AddNewEntries(
   std::string dir_path = directory_ref_->GetCreateInfo().path;
   if (dir_path[dir_path.size() - 1] != '/')
     dir_path += '/';
-  FilePath::StringType dir_file_path = UTF8StringToFilePathString(dir_path);
+  base::FilePath::StringType dir_file_path = UTF8StringToFilePathString(dir_path);
   for (std::vector<base::FileUtilProxy::Entry>::const_iterator it =
            entries.begin(); it != entries.end(); it++) {
     base::FileUtilProxy::Entry entry;
diff --git a/webkit/plugins/ppapi/ppb_file_ref_impl.cc b/webkit/plugins/ppapi/ppb_file_ref_impl.cc
index b74a4c44370f19..ec785e4eae6c12 100644
--- a/webkit/plugins/ppapi/ppb_file_ref_impl.cc
+++ b/webkit/plugins/ppapi/ppb_file_ref_impl.cc
@@ -55,10 +55,10 @@ void TrimTrailingSlash(std::string* path) {
     path->erase(path->size() - 1, 1);
 }
 
-std::string GetNameForExternalFilePath(const FilePath& in_path) {
-  const FilePath::StringType& path = in_path.value();
-  size_t pos = path.rfind(FilePath::kSeparators[0]);
-  CHECK(pos != FilePath::StringType::npos);
+std::string GetNameForExternalFilePath(const base::FilePath& in_path) {
+  const base::FilePath::StringType& path = in_path.value();
+  size_t pos = path.rfind(base::FilePath::kSeparators[0]);
+  CHECK(pos != base::FilePath::StringType::npos);
 #if defined(OS_WIN)
   return WideToUTF8(path.substr(pos + 1));
 #elif defined(OS_POSIX)
@@ -88,7 +88,7 @@ PPB_FileRef_Impl::PPB_FileRef_Impl(const PPB_FileRef_CreateInfo& info,
 }
 
 PPB_FileRef_Impl::PPB_FileRef_Impl(const PPB_FileRef_CreateInfo& info,
-                                   const FilePath& external_file_path)
+                                   const base::FilePath& external_file_path)
     : PPB_FileRef_Shared(::ppapi::OBJECT_IS_IMPL, info),
       file_system_(),
       external_file_system_path_(external_file_path) {
@@ -132,7 +132,7 @@ PPB_FileRef_Impl* PPB_FileRef_Impl::CreateInternal(PP_Resource pp_file_system,
 // static
 PPB_FileRef_Impl* PPB_FileRef_Impl::CreateExternal(
     PP_Instance instance,
-    const FilePath& external_file_path,
+    const base::FilePath& external_file_path,
     const std::string& display_name) {
   PPB_FileRef_CreateInfo info;
   info.resource = HostResource::MakeInstanceOnly(instance);
@@ -249,10 +249,10 @@ PP_Var PPB_FileRef_Impl::GetAbsolutePath() {
   return external_path_var_->GetPPVar();
 }
 
-FilePath PPB_FileRef_Impl::GetSystemPath() const {
+base::FilePath PPB_FileRef_Impl::GetSystemPath() const {
   if (GetFileSystemType() != PP_FILESYSTEMTYPE_EXTERNAL) {
     NOTREACHED();
-    return FilePath();
+    return base::FilePath();
   }
   return external_file_system_path_;
 }
diff --git a/webkit/plugins/ppapi/ppb_file_ref_impl.h b/webkit/plugins/ppapi/ppb_file_ref_impl.h
index d7bb8c523ab955..4d455a715b35f7 100644
--- a/webkit/plugins/ppapi/ppb_file_ref_impl.h
+++ b/webkit/plugins/ppapi/ppb_file_ref_impl.h
@@ -27,7 +27,7 @@ class WEBKIT_GLUE_EXPORT PPB_FileRef_Impl
   PPB_FileRef_Impl(const ::ppapi::PPB_FileRef_CreateInfo& info,
                    PPB_FileSystem_Impl* file_system);
   PPB_FileRef_Impl(const ::ppapi::PPB_FileRef_CreateInfo& info,
-                   const FilePath& external_file_path);
+                   const base::FilePath& external_file_path);
   virtual ~PPB_FileRef_Impl();
 
   // The returned object will have a refcount of 0 (just like "new").
@@ -36,7 +36,7 @@ class WEBKIT_GLUE_EXPORT PPB_FileRef_Impl
 
   // The returned object will have a refcount of 0 (just like "new").
   static PPB_FileRef_Impl* CreateExternal(PP_Instance instance,
-                                          const FilePath& external_file_path,
+                                          const base::FilePath& external_file_path,
                                           const std::string& display_name);
 
   // PPB_FileRef_API implementation (not provided by PPB_FileRef_Shared).
@@ -59,7 +59,7 @@ class WEBKIT_GLUE_EXPORT PPB_FileRef_Impl
 
   // Returns the system path corresponding to this file. Valid only for
   // external filesystems.
-  FilePath GetSystemPath() const;
+  base::FilePath GetSystemPath() const;
 
   // Returns the FileSystem API URL corresponding to this file.
   GURL GetFileSystemURL() const;
@@ -76,7 +76,7 @@ class WEBKIT_GLUE_EXPORT PPB_FileRef_Impl
   scoped_refptr<PPB_FileSystem_Impl> file_system_;
 
   // Used only for external filesystems.
-  FilePath external_file_system_path_;
+  base::FilePath external_file_system_path_;
 
   // Lazily initialized var created from the external path. This is so we can
   // return the identical string object every time it is requested.
diff --git a/webkit/plugins/ppapi/quota_file_io_unittest.cc b/webkit/plugins/ppapi/quota_file_io_unittest.cc
index 3e052a2cc5ca39..65df7d74081485 100644
--- a/webkit/plugins/ppapi/quota_file_io_unittest.cc
+++ b/webkit/plugins/ppapi/quota_file_io_unittest.cc
@@ -88,7 +88,7 @@ class QuotaFileIOTest : public PpapiUnittest {
   virtual void SetUp() OVERRIDE {
     PpapiUnittest::SetUp();
     ASSERT_TRUE(dir_.CreateUniqueTempDir());
-    FilePath path;
+    base::FilePath path;
     ASSERT_TRUE(file_util::CreateTemporaryFileInDir(dir_.path(), &path));
     int file_flags = base::PLATFORM_FILE_OPEN |
                      base::PLATFORM_FILE_READ |
diff --git a/webkit/plugins/ppapi/url_request_info_util.cc b/webkit/plugins/ppapi/url_request_info_util.cc
index 6b1f512e27ff5e..8dcad54be262e4 100644
--- a/webkit/plugins/ppapi/url_request_info_util.cc
+++ b/webkit/plugins/ppapi/url_request_info_util.cc
@@ -64,7 +64,7 @@ bool AppendFileRefToBody(
   if (!plugin_delegate)
     return false;
 
-  FilePath platform_path;
+  base::FilePath platform_path;
   switch (file_ref->GetFileSystemType()) {
     case PP_FILESYSTEMTYPE_LOCALTEMPORARY:
     case PP_FILESYSTEMTYPE_LOCALPERSISTENT:
diff --git a/webkit/plugins/webplugininfo.cc b/webkit/plugins/webplugininfo.cc
index 27c65149d463ae..a5816473ad50d7 100644
--- a/webkit/plugins/webplugininfo.cc
+++ b/webkit/plugins/webplugininfo.cc
@@ -51,7 +51,7 @@ WebPluginInfo& WebPluginInfo::operator=(const WebPluginInfo& rhs) {
 }
 
 WebPluginInfo::WebPluginInfo(const string16& fake_name,
-                             const FilePath& fake_path,
+                             const base::FilePath& fake_path,
                              const string16& fake_version,
                              const string16& fake_desc)
     : name(fake_name),
diff --git a/webkit/plugins/webplugininfo.h b/webkit/plugins/webplugininfo.h
index cc09f7804915cd..514a0463720504 100644
--- a/webkit/plugins/webplugininfo.h
+++ b/webkit/plugins/webplugininfo.h
@@ -53,7 +53,7 @@ struct WEBKIT_PLUGINS_EXPORT WebPluginInfo {
 
   // Special constructor only used during unit testing:
   WebPluginInfo(const string16& fake_name,
-                const FilePath& fake_path,
+                const base::FilePath& fake_path,
                 const string16& fake_version,
                 const string16& fake_desc);
 
@@ -61,7 +61,7 @@ struct WEBKIT_PLUGINS_EXPORT WebPluginInfo {
   string16 name;
 
   // The path to the plugin file (DLL/bundle/library).
-  FilePath path;
+  base::FilePath path;
 
   // The version number of the plugin file (may be OS-specific)
   string16 version;
diff --git a/webkit/quota/mock_quota_manager.cc b/webkit/quota/mock_quota_manager.cc
index 4904f45396dbc2..e37dc59b528b3c 100644
--- a/webkit/quota/mock_quota_manager.cc
+++ b/webkit/quota/mock_quota_manager.cc
@@ -36,7 +36,7 @@ MockQuotaManager::StorageInfo::~StorageInfo() {}
 
 MockQuotaManager::MockQuotaManager(
     bool is_incognito,
-    const FilePath& profile_path,
+    const base::FilePath& profile_path,
     base::SingleThreadTaskRunner* io_thread,
     base::SequencedTaskRunner* db_thread,
     SpecialStoragePolicy* special_storage_policy)
diff --git a/webkit/quota/mock_quota_manager.h b/webkit/quota/mock_quota_manager.h
index 013fef9cdaea27..e195e61bb199b5 100644
--- a/webkit/quota/mock_quota_manager.h
+++ b/webkit/quota/mock_quota_manager.h
@@ -31,7 +31,7 @@ namespace quota {
 class MockQuotaManager : public QuotaManager {
  public:
   MockQuotaManager(bool is_incognito,
-                   const FilePath& profile_path,
+                   const base::FilePath& profile_path,
                    base::SingleThreadTaskRunner* io_thread,
                    base::SequencedTaskRunner* db_thread,
                    SpecialStoragePolicy* special_storage_policy);
diff --git a/webkit/quota/quota_database.cc b/webkit/quota/quota_database.cc
index aaf6245a9612de..aeac4436839811 100644
--- a/webkit/quota/quota_database.cc
+++ b/webkit/quota/quota_database.cc
@@ -121,7 +121,7 @@ QuotaDatabase::OriginInfoTableEntry::OriginInfoTableEntry(
 }
 
 // QuotaDatabase ------------------------------------------------------------
-QuotaDatabase::QuotaDatabase(const FilePath& path)
+QuotaDatabase::QuotaDatabase(const base::FilePath& path)
     : db_file_path_(path),
       is_recreating_(false),
       is_disabled_(false) {
diff --git a/webkit/quota/quota_database.h b/webkit/quota/quota_database.h
index 24505597f437ad..a5c8a279a8b441 100644
--- a/webkit/quota/quota_database.h
+++ b/webkit/quota/quota_database.h
@@ -38,7 +38,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE QuotaDatabase {
   static const char kTemporaryQuotaOverrideKey[];
 
   // If 'path' is empty, an in memory database will be used.
-  explicit QuotaDatabase(const FilePath& path);
+  explicit QuotaDatabase(const base::FilePath& path);
   ~QuotaDatabase();
 
   void CloseConnection();
@@ -163,7 +163,7 @@ class WEBKIT_STORAGE_EXPORT_PRIVATE QuotaDatabase {
   bool DumpQuotaTable(QuotaTableCallback* callback);
   bool DumpOriginInfoTable(OriginInfoTableCallback* callback);
 
-  FilePath db_file_path_;
+  base::FilePath db_file_path_;
 
   scoped_ptr<sql::Connection> db_;
   scoped_ptr<sql::MetaTable> meta_table_;
diff --git a/webkit/quota/quota_database_unittest.cc b/webkit/quota/quota_database_unittest.cc
index 40e671c03a0a05..39abfac0f52f01 100644
--- a/webkit/quota/quota_database_unittest.cc
+++ b/webkit/quota/quota_database_unittest.cc
@@ -46,7 +46,7 @@ class QuotaDatabaseTest : public testing::Test {
   typedef QuotaDatabase::OriginInfoTableCallback
       OriginInfoTableCallback;
 
-  void LazyOpen(const FilePath& kDbFile) {
+  void LazyOpen(const base::FilePath& kDbFile) {
     QuotaDatabase db(kDbFile);
     EXPECT_FALSE(db.LazyOpen(false));
     ASSERT_TRUE(db.LazyOpen(true));
@@ -54,7 +54,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_TRUE(kDbFile.empty() || file_util::PathExists(kDbFile));
   }
 
-  void UpgradeSchemaV2toV3(const FilePath& kDbFile) {
+  void UpgradeSchemaV2toV3(const base::FilePath& kDbFile) {
     const QuotaTableEntry entries[] = {
       QuotaTableEntry("a", kStorageTypeTemporary,  1),
       QuotaTableEntry("b", kStorageTypeTemporary,  2),
@@ -76,7 +76,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_TRUE(verifier.table.empty());
   }
 
-  void HostQuota(const FilePath& kDbFile) {
+  void HostQuota(const base::FilePath& kDbFile) {
     QuotaDatabase db(kDbFile);
     ASSERT_TRUE(db.LazyOpen(true));
 
@@ -106,7 +106,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_FALSE(db.GetHostQuota(kHost, kStorageTypeTemporary, &quota));
   }
 
-  void GlobalQuota(const FilePath& kDbFile) {
+  void GlobalQuota(const base::FilePath& kDbFile) {
     QuotaDatabase db(kDbFile);
     ASSERT_TRUE(db.LazyOpen(true));
 
@@ -136,7 +136,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_EQ(kValue2, value);
   }
 
-  void OriginLastAccessTimeLRU(const FilePath& kDbFile) {
+  void OriginLastAccessTimeLRU(const base::FilePath& kDbFile) {
     QuotaDatabase db(kDbFile);
     ASSERT_TRUE(db.LazyOpen(true));
 
@@ -211,7 +211,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_TRUE(origin.is_empty());
   }
 
-  void OriginLastModifiedSince(const FilePath& kDbFile) {
+  void OriginLastModifiedSince(const base::FilePath& kDbFile) {
     QuotaDatabase db(kDbFile);
     ASSERT_TRUE(db.LazyOpen(true));
 
@@ -288,7 +288,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_EQ(0U, origins.count(kOrigin3));
   }
 
-  void RegisterInitialOriginInfo(const FilePath& kDbFile) {
+  void RegisterInitialOriginInfo(const base::FilePath& kDbFile) {
     QuotaDatabase db(kDbFile);
 
     const GURL kOrigins[] = {
@@ -337,7 +337,7 @@ class QuotaDatabaseTest : public testing::Test {
     }
   };
 
-  void DumpQuotaTable(const FilePath& kDbFile) {
+  void DumpQuotaTable(const base::FilePath& kDbFile) {
     QuotaTableEntry kTableEntries[] = {
       QuotaTableEntry("http://go/", kStorageTypeTemporary, 1),
       QuotaTableEntry("http://oo/", kStorageTypeTemporary, 2),
@@ -360,7 +360,7 @@ class QuotaDatabaseTest : public testing::Test {
     EXPECT_TRUE(verifier.table.empty());
   }
 
-  void DumpOriginInfoTable(const FilePath& kDbFile) {
+  void DumpOriginInfoTable(const base::FilePath& kDbFile) {
     base::Time now(base::Time::Now());
     typedef QuotaDatabase::OriginInfoTableEntry Entry;
     Entry kTableEntries[] = {
@@ -426,7 +426,7 @@ class QuotaDatabaseTest : public testing::Test {
     }
   }
 
-  bool OpenDatabase(sql::Connection* db, const FilePath& kDbFile) {
+  bool OpenDatabase(sql::Connection* db, const base::FilePath& kDbFile) {
     if (kDbFile.empty()) {
       return db->OpenInMemory();
     }
@@ -440,7 +440,7 @@ class QuotaDatabaseTest : public testing::Test {
 
   // Create V2 database and populate some data.
   void CreateV2Database(
-      const FilePath& kDbFile,
+      const base::FilePath& kDbFile,
       const QuotaTableEntry* entries,
       size_t entries_size) {
     scoped_ptr<sql::Connection> db(new sql::Connection);
@@ -495,55 +495,55 @@ class QuotaDatabaseTest : public testing::Test {
 TEST_F(QuotaDatabaseTest, LazyOpen) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   LazyOpen(kDbFile);
-  LazyOpen(FilePath());
+  LazyOpen(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, UpgradeSchema) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   UpgradeSchemaV2toV3(kDbFile);
 }
 
 TEST_F(QuotaDatabaseTest, HostQuota) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   HostQuota(kDbFile);
-  HostQuota(FilePath());
+  HostQuota(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, GlobalQuota) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   GlobalQuota(kDbFile);
-  GlobalQuota(FilePath());
+  GlobalQuota(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, OriginLastAccessTimeLRU) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   OriginLastAccessTimeLRU(kDbFile);
-  OriginLastAccessTimeLRU(FilePath());
+  OriginLastAccessTimeLRU(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, OriginLastModifiedSince) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   OriginLastModifiedSince(kDbFile);
-  OriginLastModifiedSince(FilePath());
+  OriginLastModifiedSince(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, BootstrapFlag) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
 
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   QuotaDatabase db(kDbFile);
 
   EXPECT_FALSE(db.IsOriginDatabaseBootstrapped());
@@ -556,24 +556,24 @@ TEST_F(QuotaDatabaseTest, BootstrapFlag) {
 TEST_F(QuotaDatabaseTest, RegisterInitialOriginInfo) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   RegisterInitialOriginInfo(kDbFile);
-  RegisterInitialOriginInfo(FilePath());
+  RegisterInitialOriginInfo(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, DumpQuotaTable) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   DumpQuotaTable(kDbFile);
-  DumpQuotaTable(FilePath());
+  DumpQuotaTable(base::FilePath());
 }
 
 TEST_F(QuotaDatabaseTest, DumpOriginInfoTable) {
   base::ScopedTempDir data_dir;
   ASSERT_TRUE(data_dir.CreateUniqueTempDir());
-  const FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
+  const base::FilePath kDbFile = data_dir.path().AppendASCII("quota_manager.db");
   DumpOriginInfoTable(kDbFile);
-  DumpOriginInfoTable(FilePath());
+  DumpOriginInfoTable(base::FilePath());
 }
 }  // namespace quota
diff --git a/webkit/quota/quota_manager.cc b/webkit/quota/quota_manager.cc
index 0d875f035194d4..1801372a5e1d8e 100644
--- a/webkit/quota/quota_manager.cc
+++ b/webkit/quota/quota_manager.cc
@@ -151,7 +151,7 @@ bool UpdateModifiedTimeOnDBThread(const GURL& origin,
   return database->SetOriginLastModifiedTime(origin, type, modified_time);
 }
 
-int64 CallSystemGetAmountOfFreeDiskSpace(const FilePath& profile_path) {
+int64 CallSystemGetAmountOfFreeDiskSpace(const base::FilePath& profile_path) {
   // Ensure the profile path exists.
   if(!file_util::CreateDirectory(profile_path)) {
     LOG(WARNING) << "Create directory failed for path" << profile_path.value();
@@ -876,7 +876,7 @@ class QuotaManager::DumpOriginInfoTableHelper {
 // QuotaManager ---------------------------------------------------------------
 
 QuotaManager::QuotaManager(bool is_incognito,
-                           const FilePath& profile_path,
+                           const base::FilePath& profile_path,
                            base::SingleThreadTaskRunner* io_thread,
                            base::SequencedTaskRunner* db_thread,
                            SpecialStoragePolicy* special_storage_policy)
@@ -1183,7 +1183,7 @@ void QuotaManager::LazyInitialize() {
   }
 
   // Use an empty path to open an in-memory only databse for incognito.
-  database_.reset(new QuotaDatabase(is_incognito_ ? FilePath() :
+  database_.reset(new QuotaDatabase(is_incognito_ ? base::FilePath() :
       profile_path_.AppendASCII(kDatabaseName)));
 
   temporary_usage_tracker_.reset(
diff --git a/webkit/quota/quota_manager.h b/webkit/quota/quota_manager.h
index 62f21d286f0409..b8d9e1895a5043 100644
--- a/webkit/quota/quota_manager.h
+++ b/webkit/quota/quota_manager.h
@@ -26,9 +26,8 @@
 #include "webkit/quota/special_storage_policy.h"
 #include "webkit/storage/webkit_storage_export.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class SequencedTaskRunner;
 class SingleThreadTaskRunner;
 }
@@ -106,7 +105,7 @@ class WEBKIT_STORAGE_EXPORT QuotaManager
   static const int64 kNoLimit;
 
   QuotaManager(bool is_incognito,
-               const FilePath& profile_path,
+               const base::FilePath& profile_path,
                base::SingleThreadTaskRunner* io_thread,
                base::SequencedTaskRunner* db_thread,
                SpecialStoragePolicy* special_storage_policy);
@@ -246,7 +245,7 @@ class WEBKIT_STORAGE_EXPORT QuotaManager
 
   // Function pointer type used to store the function which returns the
   // available disk space for the disk containing the given FilePath.
-  typedef int64 (*GetAvailableDiskSpaceFn)(const FilePath&);
+  typedef int64 (*GetAvailableDiskSpaceFn)(const base::FilePath&);
 
   typedef base::Callback<void(const QuotaTableEntries&)>
       DumpQuotaTableCallback;
@@ -365,7 +364,7 @@ class WEBKIT_STORAGE_EXPORT QuotaManager
       const base::Callback<void(bool)>& reply);
 
   const bool is_incognito_;
-  const FilePath profile_path_;
+  const base::FilePath profile_path_;
 
   scoped_refptr<QuotaManagerProxy> proxy_;
   bool db_disabled_;
diff --git a/webkit/quota/quota_manager_unittest.cc b/webkit/quota/quota_manager_unittest.cc
index 49476d0601ea2d..0f800a2a8f1365 100644
--- a/webkit/quota/quota_manager_unittest.cc
+++ b/webkit/quota/quota_manager_unittest.cc
@@ -35,7 +35,7 @@ const StorageType kSync = kStorageTypeSyncable;
 const int kAllClients = QuotaClient::kAllClientsMask;
 
 // Returns a deterministic value for the amount of available disk space.
-int64 GetAvailableDiskSpaceForTest(const FilePath&) {
+int64 GetAvailableDiskSpaceForTest(const base::FilePath&) {
   return 13377331;
 }
 
@@ -393,7 +393,7 @@ class QuotaManagerTest : public testing::Test {
   const OriginInfoTableEntries& origin_info_entries() const {
     return origin_info_entries_;
   }
-  FilePath profile_path() const { return data_dir_.path(); }
+  base::FilePath profile_path() const { return data_dir_.path(); }
   int status_callback_count() const { return status_callback_count_; }
   void reset_status_callback_count() { status_callback_count_ = 0; }
 
diff --git a/webkit/support/platform_support_android.cc b/webkit/support/platform_support_android.cc
index f6bf077361e80c..30effc72ed625a 100644
--- a/webkit/support/platform_support_android.cc
+++ b/webkit/support/platform_support_android.cc
@@ -36,7 +36,7 @@ void BeforeInitialize(bool unit_test_mode) {
   base::InitAndroidTestPaths();
 
   // Place cache under kDumpRenderTreeDir to allow the NRWT script to clear it.
-  FilePath path(kDumpRenderTreeDir);
+  base::FilePath path(kDumpRenderTreeDir);
   path = path.Append("cache");
   PathService::Override(base::DIR_CACHE, path);
 
@@ -57,7 +57,7 @@ void BeforeInitialize(bool unit_test_mode) {
 }
 
 void AfterInitialize(bool unit_test_mode) {
-  FilePath data_path(kDumpRenderTreeDir);
+  base::FilePath data_path(kDumpRenderTreeDir);
   data_path = data_path.Append("DumpRenderTree.pak");
   ResourceBundle::InitSharedInstanceWithPakPath(data_path);
 
@@ -96,13 +96,13 @@ string16 TestWebKitPlatformSupport::GetLocalizedString(int message_id) {
 base::StringPiece TestWebKitPlatformSupport::GetDataResource(
     int resource_id,
     ui::ScaleFactor scale_factor) {
-  FilePath resources_path(kDumpRenderTreeDir);
+  base::FilePath resources_path(kDumpRenderTreeDir);
   resources_path = resources_path.Append("DumpRenderTree_resources");
   switch (resource_id) {
     case IDR_BROKENIMAGE: {
       CR_DEFINE_STATIC_LOCAL(std::string, broken_image_data, ());
       if (broken_image_data.empty()) {
-        FilePath path = resources_path.Append("missingImage.gif");
+        base::FilePath path = resources_path.Append("missingImage.gif");
         bool success = file_util::ReadFileToString(path, &broken_image_data);
         if (!success)
           LOG(FATAL) << "Failed reading: " << path.value();
@@ -112,7 +112,7 @@ base::StringPiece TestWebKitPlatformSupport::GetDataResource(
     case IDR_TEXTAREA_RESIZER: {
       CR_DEFINE_STATIC_LOCAL(std::string, resize_corner_data, ());
       if (resize_corner_data.empty()) {
-        FilePath path = resources_path.Append("textAreaResizeCorner.png");
+        base::FilePath path = resources_path.Append("textAreaResizeCorner.png");
         bool success = file_util::ReadFileToString(path, &resize_corner_data);
         if (!success)
           LOG(FATAL) << "Failed reading: " << path.value();
diff --git a/webkit/support/platform_support_linux.cc b/webkit/support/platform_support_linux.cc
index fa795f91f05b5d..a26c5f460010b2 100644
--- a/webkit/support/platform_support_linux.cc
+++ b/webkit/support/platform_support_linux.cc
@@ -23,7 +23,7 @@ void BeforeInitialize(bool unit_test_mode) {
 }
 
 void AfterInitialize(bool unit_test_mode) {
-  FilePath data_path;
+  base::FilePath data_path;
   PathService::Get(base::DIR_EXE, &data_path);
   data_path = data_path.Append("DumpRenderTree.pak");
   ResourceBundle::InitSharedInstanceWithPakPath(data_path);
@@ -45,14 +45,14 @@ string16 TestWebKitPlatformSupport::GetLocalizedString(int message_id) {
 base::StringPiece TestWebKitPlatformSupport::GetDataResource(
     int resource_id,
     ui::ScaleFactor scale_factor) {
-  FilePath resources_path;
+  base::FilePath resources_path;
   PathService::Get(base::DIR_EXE, &resources_path);
   resources_path = resources_path.Append("DumpRenderTree_resources");
   switch (resource_id) {
     case IDR_BROKENIMAGE: {
       CR_DEFINE_STATIC_LOCAL(std::string, broken_image_data, ());
       if (broken_image_data.empty()) {
-        FilePath path = resources_path.Append("missingImage.gif");
+        base::FilePath path = resources_path.Append("missingImage.gif");
         bool success = file_util::ReadFileToString(path, &broken_image_data);
         if (!success)
           LOG(FATAL) << "Failed reading: " << path.value();
@@ -62,7 +62,7 @@ base::StringPiece TestWebKitPlatformSupport::GetDataResource(
     case IDR_TEXTAREA_RESIZER: {
       CR_DEFINE_STATIC_LOCAL(std::string, resize_corner_data, ());
       if (resize_corner_data.empty()) {
-        FilePath path = resources_path.Append("textAreaResizeCorner.png");
+        base::FilePath path = resources_path.Append("textAreaResizeCorner.png");
         bool success = file_util::ReadFileToString(path, &resize_corner_data);
         if (!success)
           LOG(FATAL) << "Failed reading: " << path.value();
diff --git a/webkit/support/platform_support_mac.mm b/webkit/support/platform_support_mac.mm
index 9a758ec983636b..2681cb4c3150dd 100644
--- a/webkit/support/platform_support_mac.mm
+++ b/webkit/support/platform_support_mac.mm
@@ -101,7 +101,7 @@ static void SwizzleNSPasteboard() {
 void AfterInitialize(bool unit_test_mode) {
   // Load a data pack.
   g_resource_data_pack = new ui::DataPack(ui::SCALE_FACTOR_100P);
-  FilePath resources_pak_path;
+  base::FilePath resources_pak_path;
   if (unit_test_mode) {
     PathService::Get(base::DIR_EXE, &resources_pak_path);
     resources_pak_path = resources_pak_path.Append("DumpRenderTree.app")
@@ -112,7 +112,7 @@ void AfterInitialize(bool unit_test_mode) {
     NSString* resource_path =
         [base::mac::FrameworkBundle() pathForResource:@"DumpRenderTree"
                                                ofType:@"pak"];
-    resources_pak_path = FilePath([resource_path fileSystemRepresentation]);
+    resources_pak_path = base::FilePath([resource_path fileSystemRepresentation]);
   }
   if (!g_resource_data_pack->LoadFromPath(resources_pak_path)) {
     LOG(FATAL) << "failed to load DumpRenderTree.pak";
@@ -156,7 +156,7 @@ void AfterInitialize(bool unit_test_mode) {
 
   // Add <app bundle's parent dir>/plugins to the plugin path so we can load
   // test plugins.
-  FilePath plugins_dir;
+  base::FilePath plugins_dir;
   PathService::Get(base::DIR_EXE, &plugins_dir);
   plugins_dir = plugins_dir.AppendASCII("../../../plugins");
   webkit::npapi::PluginList::Singleton()->AddExtraPluginDir(plugins_dir);
@@ -202,14 +202,14 @@ void AfterShutdown() {
 }
 
 // Helper method for getting the path to the test shell resources directory.
-static FilePath GetResourcesFilePath() {
-  FilePath path;
+static base::FilePath GetResourcesFilePath() {
+  base::FilePath path;
   // We assume the application is bundled.
   if (!base::mac::AmIBundled()) {
     LOG(FATAL) << "Failed to locate resources. The applicaiton is not bundled.";
   }
   PathService::Get(base::DIR_EXE, &path);
-  path = path.Append(FilePath::kParentDirectory);
+  path = path.Append(base::FilePath::kParentDirectory);
   return path.AppendASCII("Resources");
 }
 
@@ -221,7 +221,7 @@ static FilePath GetResourcesFilePath() {
     // Use webkit's broken image icon (16x16)
     CR_DEFINE_STATIC_LOCAL(std::string, broken_image_data, ());
     if (broken_image_data.empty()) {
-      FilePath path = GetResourcesFilePath();
+      base::FilePath path = GetResourcesFilePath();
       // In order to match WebKit's colors for the missing image, we have to
       // use a PNG. The GIF doesn't have the color range needed to correctly
       // match the TIFF they use in Safari.
@@ -238,7 +238,7 @@ static FilePath GetResourcesFilePath() {
     // Use webkit's text area resizer image.
     CR_DEFINE_STATIC_LOCAL(std::string, resize_corner_data, ());
     if (resize_corner_data.empty()) {
-      FilePath path = GetResourcesFilePath();
+      base::FilePath path = GetResourcesFilePath();
       path = path.AppendASCII("textAreaResizeCorner.png");
       file_util::AbsolutePath(&path);
       bool success = file_util::ReadFileToString(path, &resize_corner_data);
diff --git a/webkit/support/platform_support_win.cc b/webkit/support/platform_support_win.cc
index 249a5338f92ae5..f1c61b9e4ca576 100644
--- a/webkit/support/platform_support_win.cc
+++ b/webkit/support/platform_support_win.cc
@@ -20,8 +20,8 @@
 
 namespace {
 
-FilePath GetResourceFilePath(const char* ascii_name) {
-  FilePath path;
+base::FilePath GetResourceFilePath(const char* ascii_name) {
+  base::FilePath path;
   PathService::Get(base::DIR_EXE, &path);
   path = path.AppendASCII("DumpRenderTree_resources");
   return path.AppendASCII(ascii_name);
@@ -80,7 +80,7 @@ base::StringPiece TestWebKitPlatformSupport::GetDataResource(
     // Use webkit's broken image icon (16x16)
     static std::string broken_image_data;
     if (broken_image_data.empty()) {
-      FilePath path = GetResourceFilePath("missingImage.gif");
+      base::FilePath path = GetResourceFilePath("missingImage.gif");
       bool success = file_util::ReadFileToString(path, &broken_image_data);
       if (!success) {
         LOG(FATAL) << "Failed reading: " << path.value();
@@ -92,7 +92,7 @@ base::StringPiece TestWebKitPlatformSupport::GetDataResource(
     // Use webkit's text area resizer image.
     static std::string resize_corner_data;
     if (resize_corner_data.empty()) {
-      FilePath path = GetResourceFilePath("textAreaResizeCorner.png");
+      base::FilePath path = GetResourceFilePath("textAreaResizeCorner.png");
       bool success = file_util::ReadFileToString(path, &resize_corner_data);
       if (!success) {
         LOG(FATAL) << "Failed reading: " << path.value();
diff --git a/webkit/support/simple_database_system.cc b/webkit/support/simple_database_system.cc
index c8b5a024fe93de..88e088c46500bd 100644
--- a/webkit/support/simple_database_system.cc
+++ b/webkit/support/simple_database_system.cc
@@ -221,7 +221,7 @@ void SimpleDatabaseSystem::VfsOpenFile(
     const string16& vfs_file_name, int desired_flags,
     base::PlatformFile* file_handle, base::WaitableEvent* done_event ) {
   DCHECK(db_thread_proxy_->BelongsToCurrentThread());
-  FilePath file_name = GetFullFilePathForVfsFile(vfs_file_name);
+  base::FilePath file_name = GetFullFilePathForVfsFile(vfs_file_name);
   if (file_name.empty()) {
     VfsBackend::OpenTempFileInDirectory(
         db_tracker_->DatabaseDirectory(), desired_flags, file_handle);
@@ -241,7 +241,7 @@ void SimpleDatabaseSystem::VfsDeleteFile(
   const int kNumDeleteRetries = 3;
   int num_retries = 0;
   *result = SQLITE_OK;
-  FilePath file_name = GetFullFilePathForVfsFile(vfs_file_name);
+  base::FilePath file_name = GetFullFilePathForVfsFile(vfs_file_name);
   do {
     *result = VfsBackend::DeleteFile(file_name, sync_dir);
   } while ((++num_retries < kNumDeleteRetries) &&
@@ -287,11 +287,11 @@ void SimpleDatabaseSystem::VfsGetSpaceAvailable(
   done_event->Signal();
 }
 
-FilePath SimpleDatabaseSystem::GetFullFilePathForVfsFile(
+base::FilePath SimpleDatabaseSystem::GetFullFilePathForVfsFile(
     const string16& vfs_file_name) {
   DCHECK(db_thread_proxy_->BelongsToCurrentThread());
   if (vfs_file_name.empty())  // temp file, used for vacuuming
-    return FilePath();
+    return base::FilePath();
   return DatabaseUtil::GetFullFilePathForVfsFile(
       db_tracker_.get(), vfs_file_name);
 }
diff --git a/webkit/support/simple_database_system.h b/webkit/support/simple_database_system.h
index bd92fc2bbd1357..3fef6f8fb35940 100644
--- a/webkit/support/simple_database_system.h
+++ b/webkit/support/simple_database_system.h
@@ -80,7 +80,7 @@ class SimpleDatabaseSystem : public webkit_database::DatabaseTracker::Observer,
   void VfsGetSpaceAvailable(const string16& origin_identifier,
                             int64* result, base::WaitableEvent* done_event);
 
-  FilePath GetFullFilePathForVfsFile(const string16& vfs_file_name);
+  base::FilePath GetFullFilePathForVfsFile(const string16& vfs_file_name);
 
   void ResetTracker();
   void ThreadCleanup(base::WaitableEvent* done_event);
diff --git a/webkit/support/test_webkit_platform_support.cc b/webkit/support/test_webkit_platform_support.cc
index a6cf5a94a771c6..750b32b4886e71 100644
--- a/webkit/support/test_webkit_platform_support.cc
+++ b/webkit/support/test_webkit_platform_support.cc
@@ -92,7 +92,7 @@ TestWebKitPlatformSupport::TestWebKitPlatformSupport(bool unit_test_mode,
 
   // Load libraries for media and enable the media player.
   bool enable_media = false;
-  FilePath module_path;
+  base::FilePath module_path;
   if (PathService::Get(base::DIR_MODULE, &module_path)) {
 #if defined(OS_MACOSX)
     if (base::mac::AmIBundled())
@@ -141,7 +141,7 @@ TestWebKitPlatformSupport::TestWebKitPlatformSupport(bool unit_test_mode,
 
   // Initializing with a default context, which means no on-disk cookie DB,
   // and no support for directory listings.
-  SimpleResourceLoaderBridge::Init(FilePath(), cache_mode, true);
+  SimpleResourceLoaderBridge::Init(base::FilePath(), cache_mode, true);
 
   // Test shell always exposes the GC.
   webkit_glue::SetJavaScriptFlags(" --expose-gc");
@@ -483,7 +483,7 @@ void TestWebKitPlatformSupport::GetPlugins(
   webkit::npapi::PluginList::Singleton()->GetPlugins(plugins);
   // Don't load the forked npapi_layout_test_plugin in DRT, we only want to
   // use the upstream version TestNetscapePlugIn.
-  const FilePath::StringType kPluginBlackList[] = {
+  const base::FilePath::StringType kPluginBlackList[] = {
     FILE_PATH_LITERAL("npapi_layout_test_plugin.dll"),
     FILE_PATH_LITERAL("WebKitTestNetscapePlugIn.plugin"),
     FILE_PATH_LITERAL("libnpapi_layout_test_plugin.so"),
@@ -491,7 +491,7 @@ void TestWebKitPlatformSupport::GetPlugins(
   for (int i = plugins->size() - 1; i >= 0; --i) {
     webkit::WebPluginInfo plugin_info = plugins->at(i);
     for (size_t j = 0; j < arraysize(kPluginBlackList); ++j) {
-      if (plugin_info.path.BaseName() == FilePath(kPluginBlackList[j])) {
+      if (plugin_info.path.BaseName() == base::FilePath(kPluginBlackList[j])) {
         plugins->erase(plugins->begin() + i);
       }
     }
@@ -546,7 +546,7 @@ size_t TestWebKitPlatformSupport::computeLastHyphenLocation(
   if (!hyphen_dictionary_) {
     // Initialize the hyphen library with a sample dictionary. To avoid test
     // flakiness, this code synchronously loads the dictionary.
-    FilePath path = webkit_support::GetChromiumRootDirFilePath();
+    base::FilePath path = webkit_support::GetChromiumRootDirFilePath();
     path = path.Append(FILE_PATH_LITERAL("third_party/hyphen/hyph_en_US.dic"));
     std::string dictionary;
     if (!file_util::ReadFileToString(path, &dictionary))
diff --git a/webkit/support/test_webkit_platform_support.h b/webkit/support/test_webkit_platform_support.h
index 6e2dc6eaba1efe..ec43ce51b5e852 100644
--- a/webkit/support/test_webkit_platform_support.h
+++ b/webkit/support/test_webkit_platform_support.h
@@ -90,7 +90,7 @@ class TestWebKitPlatformSupport :
     return &url_loader_factory_;
   }
 
-  const FilePath& file_system_root() const {
+  const base::FilePath& file_system_root() const {
     return file_system_root_.path();
   }
 
diff --git a/webkit/support/test_webplugin_page_delegate.cc b/webkit/support/test_webplugin_page_delegate.cc
index 36ac1d8983be78..99686f13ec32f8 100644
--- a/webkit/support/test_webplugin_page_delegate.cc
+++ b/webkit/support/test_webplugin_page_delegate.cc
@@ -11,13 +11,13 @@ namespace webkit_support {
 
 webkit::npapi::WebPluginDelegate*
 TestWebPluginPageDelegate::CreatePluginDelegate(
-    const FilePath& file_path,
+    const base::FilePath& file_path,
     const std::string& mime_type) {
   return webkit::npapi::WebPluginDelegateImpl::Create(file_path, mime_type);
 }
 
 WebKit::WebPlugin* TestWebPluginPageDelegate::CreatePluginReplacement(
-    const FilePath& file_path) {
+    const base::FilePath& file_path) {
   return NULL;
 }
 
diff --git a/webkit/support/test_webplugin_page_delegate.h b/webkit/support/test_webplugin_page_delegate.h
index 3949af7b4af465..b861a050373cac 100644
--- a/webkit/support/test_webplugin_page_delegate.h
+++ b/webkit/support/test_webplugin_page_delegate.h
@@ -18,10 +18,10 @@ class TestWebPluginPageDelegate : public webkit::npapi::WebPluginPageDelegate {
   virtual ~TestWebPluginPageDelegate() {}
 
   virtual webkit::npapi::WebPluginDelegate* CreatePluginDelegate(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       const std::string& mime_type) OVERRIDE;
   virtual WebKit::WebPlugin* CreatePluginReplacement(
-      const FilePath& file_path) OVERRIDE;
+      const base::FilePath& file_path) OVERRIDE;
   virtual void CreatedPluginWindow(gfx::PluginWindowHandle handle) OVERRIDE {}
   virtual void WillDestroyPluginWindow(
       gfx::PluginWindowHandle handle) OVERRIDE {}
diff --git a/webkit/support/webkit_support.cc b/webkit/support/webkit_support.cc
index 9e376272ddc465..66b98310563dfa 100644
--- a/webkit/support/webkit_support.cc
+++ b/webkit/support/webkit_support.cc
@@ -123,7 +123,7 @@ void InitLogging() {
   // On Android we expect the log to appear in logcat.
   base::InitAndroidTestLogging();
 #else
-  FilePath log_filename;
+  base::FilePath log_filename;
   PathService::Get(base::DIR_EXE, &log_filename);
   log_filename = log_filename.AppendASCII("DumpRenderTree.log");
   logging::InitLogging(
@@ -215,11 +215,11 @@ class TestEnvironment {
   // in SetCurrentDirectoryForFileURL() and GetAbsoluteWebStringFromUTF8Path(),
   // as the directory might not exist on the device because we are using
   // file-over-http bridge.
-  void set_mock_current_directory(const FilePath& directory) {
+  void set_mock_current_directory(const base::FilePath& directory) {
     mock_current_directory_ = directory;
   }
 
-  FilePath mock_current_directory() const {
+  base::FilePath mock_current_directory() const {
     return mock_current_directory_;
   }
 
@@ -240,7 +240,7 @@ class TestEnvironment {
   scoped_ptr<TestWebKitPlatformSupport> webkit_platform_support_;
 
 #if defined(OS_ANDROID)
-  FilePath mock_current_directory_;
+  base::FilePath mock_current_directory_;
   scoped_ptr<webkit_media::WebMediaPlayerManagerAndroid> media_player_manager_;
   scoped_ptr<webkit_media::MediaPlayerBridgeManagerImpl> media_bridge_manager_;
 #endif
@@ -253,7 +253,7 @@ class WebPluginImplWithPageDelegate
  public:
   WebPluginImplWithPageDelegate(WebFrame* frame,
                                 const WebPluginParams& params,
-                                const FilePath& path)
+                                const base::FilePath& path)
       : webkit_support::TestWebPluginPageDelegate(),
         webkit::npapi::WebPluginImpl(frame, params, path, AsWeakPtr()) {}
   virtual ~WebPluginImplWithPageDelegate() {}
@@ -261,8 +261,8 @@ class WebPluginImplWithPageDelegate
   DISALLOW_COPY_AND_ASSIGN(WebPluginImplWithPageDelegate);
 };
 
-FilePath GetWebKitRootDirFilePath() {
-  FilePath basePath;
+base::FilePath GetWebKitRootDirFilePath() {
+  base::FilePath basePath;
   PathService::Get(base::DIR_SOURCE_ROOT, &basePath);
   if (file_util::PathExists(
           basePath.Append(FILE_PATH_LITERAL("third_party/WebKit")))) {
@@ -353,8 +353,8 @@ void SetUpTestEnvironmentImpl(bool unit_test_mode,
 
 namespace webkit_support {
 
-FilePath GetChromiumRootDirFilePath() {
-  FilePath basePath;
+base::FilePath GetChromiumRootDirFilePath() {
+  base::FilePath basePath;
   PathService::Get(base::DIR_SOURCE_ROOT, &basePath);
   if (file_util::PathExists(
           basePath.Append(FILE_PATH_LITERAL("third_party/WebKit")))) {
@@ -480,7 +480,7 @@ WebKit::WebStorageNamespace* CreateSessionStorageNamespace(unsigned quota) {
 }
 
 WebKit::WebString GetWebKitRootDir() {
-  FilePath path = GetWebKitRootDirFilePath();
+  base::FilePath path = GetWebKitRootDirFilePath();
   std::string path_ascii = path.MaybeAsASCII();
   CHECK(!path_ascii.empty());
   return WebKit::WebString::fromUTF8(path_ascii.c_str());
@@ -619,11 +619,11 @@ void PostDelayedTask(TaskAdaptor* task, int64 delay_ms) {
 
 WebString GetAbsoluteWebStringFromUTF8Path(const std::string& utf8_path) {
 #if defined(OS_WIN)
-  FilePath path(UTF8ToWide(utf8_path));
+  base::FilePath path(UTF8ToWide(utf8_path));
   file_util::AbsolutePath(&path);
   return WebString(path.value());
 #else
-  FilePath path(base::SysWideToNativeMB(base::SysUTF8ToWide(utf8_path)));
+  base::FilePath path(base::SysWideToNativeMB(base::SysUTF8ToWide(utf8_path)));
 #if defined(OS_ANDROID)
   if (WebKit::layoutTestMode()) {
     // See comment of TestEnvironment::set_mock_current_directory().
@@ -655,9 +655,9 @@ WebURL CreateURLForPathOrURL(const std::string& path_or_url_in_nativemb) {
   if (url.is_valid() && url.has_scheme())
     return WebURL(url);
 #if defined(OS_WIN)
-  FilePath path(wide_path_or_url);
+  base::FilePath path(wide_path_or_url);
 #else
-  FilePath path(path_or_url_in_nativemb);
+  base::FilePath path(path_or_url_in_nativemb);
 #endif
   file_util::AbsolutePath(&path);
   return net::FilePathToFileURL(path);
@@ -670,7 +670,7 @@ WebURL RewriteLayoutTestsURL(const std::string& utf8_url) {
   if (utf8_url.compare(0, kPrefixLen, kPrefix, kPrefixLen))
     return WebURL(GURL(utf8_url));
 
-  FilePath replacePath =
+  base::FilePath replacePath =
       GetWebKitRootDirFilePath().Append(FILE_PATH_LITERAL("LayoutTests/"));
 
   // On Android, the file is actually accessed through file-over-http. Disable
@@ -692,14 +692,14 @@ WebURL RewriteLayoutTestsURL(const std::string& utf8_url) {
 }
 
 bool SetCurrentDirectoryForFileURL(const WebKit::WebURL& fileUrl) {
-  FilePath local_path;
+  base::FilePath local_path;
   if (!net::FileURLToFilePath(fileUrl, &local_path))
     return false;
 #if defined(OS_ANDROID)
   if (WebKit::layoutTestMode()) {
     // See comment of TestEnvironment::set_mock_current_directory().
     DCHECK(test_environment);
-    FilePath directory = local_path.DirName();
+    base::FilePath directory = local_path.DirName();
     test_environment->set_mock_current_directory(directory);
     // Still try to actually change the directory, but ignore any error.
     // For a few tests that need to access resources directly as files
@@ -712,7 +712,7 @@ bool SetCurrentDirectoryForFileURL(const WebKit::WebURL& fileUrl) {
 }
 
 WebURL LocalFileToDataURL(const WebURL& fileUrl) {
-  FilePath local_path;
+  base::FilePath local_path;
   if (!net::FileURLToFilePath(fileUrl, &local_path))
     return WebURL();
 
@@ -834,7 +834,7 @@ WebKit::WebThemeEngine* GetThemeEngine() {
 
 // DevTools frontend path for inspector LayoutTests.
 WebURL GetDevToolsPathAsURL() {
-  FilePath dirExe;
+  base::FilePath dirExe;
   if (!PathService::Get(base::DIR_EXE, &dirExe)) {
       DCHECK(false);
       return WebURL();
@@ -842,7 +842,7 @@ WebURL GetDevToolsPathAsURL() {
 #if defined(OS_MACOSX)
   dirExe = dirExe.AppendASCII("../../..");
 #endif
-  FilePath devToolsPath = dirExe.AppendASCII(
+  base::FilePath devToolsPath = dirExe.AppendASCII(
       "resources/inspector/devtools.html");
   return net::FilePathToFileURL(devToolsPath);
 }
@@ -866,7 +866,7 @@ WebKit::WebString RegisterIsolatedFileSystem(
     const WebKit::WebVector<WebKit::WebString>& filenames) {
   fileapi::IsolatedContext::FileInfoSet files;
   for (size_t i = 0; i < filenames.size(); ++i) {
-    FilePath path = webkit_base::WebStringToFilePath(filenames[i]);
+    base::FilePath path = webkit_base::WebStringToFilePath(filenames[i]);
     files.AddPath(path, NULL);
   }
   std::string filesystemId =
diff --git a/webkit/support/webkit_support.h b/webkit/support/webkit_support.h
index 3120d0bcccf0bf..5ff2558b617d5a 100644
--- a/webkit/support/webkit_support.h
+++ b/webkit/support/webkit_support.h
@@ -17,7 +17,9 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDevToolsAgentClient.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace WebKit {
 class WebApplicationCacheHost;
@@ -56,7 +58,7 @@ namespace webkit_support {
 // webkit-in-chromium build, this is the root directory of the checkout. In a
 // standalone webkit build, it is Source/WebKit/chromium relative from the
 // checkout's root directory.
-FilePath GetChromiumRootDirFilePath();
+base::FilePath GetChromiumRootDirFilePath();
 
 // Initializes or terminates a test environment.
 // |unit_test_mode| should be set to true when running in a TestSuite, in which
diff --git a/webkit/support/weburl_loader_mock_factory.cc b/webkit/support/weburl_loader_mock_factory.cc
index 43b15e4574d9f7..11da208e0d19f0 100644
--- a/webkit/support/weburl_loader_mock_factory.cc
+++ b/webkit/support/weburl_loader_mock_factory.cc
@@ -25,7 +25,7 @@ using WebKit::WebURLResponse;
 
 struct WebURLLoaderMockFactory::ResponseInfo {
   WebKit::WebURLResponse response;
-  FilePath file_path;
+  base::FilePath file_path;
 };
 
 WebURLLoaderMockFactory::WebURLLoaderMockFactory() {}
@@ -41,10 +41,10 @@ void WebURLLoaderMockFactory::RegisterURL(const WebURL& url,
 #if defined(OS_POSIX)
     // TODO(jcivelli): On Linux, UTF8 might not be correct.
     response_info.file_path =
-        FilePath(static_cast<std::string>(file_path.utf8()));
+        base::FilePath(static_cast<std::string>(file_path.utf8()));
 #elif defined(OS_WIN)
     response_info.file_path =
-        FilePath(std::wstring(file_path.data(), file_path.length()));
+        base::FilePath(std::wstring(file_path.data(), file_path.length()));
 #endif
     DCHECK(file_util::PathExists(response_info.file_path))
         << response_info.file_path.MaybeAsASCII() << " does not exist.";
@@ -176,7 +176,7 @@ bool WebURLLoaderMockFactory::IsPending(WebURLLoaderMock* loader) {
 }
 
 // static
-bool WebURLLoaderMockFactory::ReadFile(const FilePath& file_path,
+bool WebURLLoaderMockFactory::ReadFile(const base::FilePath& file_path,
                                        WebData* data) {
   int64 file_size = 0;
   if (!file_util::GetFileSize(file_path, &file_size))
diff --git a/webkit/support/weburl_loader_mock_factory.h b/webkit/support/weburl_loader_mock_factory.h
index 310dbbc378234a..85fe0cc0203439 100644
--- a/webkit/support/weburl_loader_mock_factory.h
+++ b/webkit/support/weburl_loader_mock_factory.h
@@ -89,7 +89,7 @@ class WebURLLoaderMockFactory {
 
   // Reads |m_filePath| and puts its content in |data|.
   // Returns true if it successfully read the file.
-  static bool ReadFile(const FilePath& file_path, WebKit::WebData* data);
+  static bool ReadFile(const base::FilePath& file_path, WebKit::WebData* data);
 
   // The loaders that have not being served data yet.
   typedef std::map<WebURLLoaderMock*, WebKit::WebURLRequest> LoaderToRequestMap;
diff --git a/webkit/tools/test_shell/image_decoder_unittest.cc b/webkit/tools/test_shell/image_decoder_unittest.cc
index 849d1b2960bd70..0458af217cfcb2 100644
--- a/webkit/tools/test_shell/image_decoder_unittest.cc
+++ b/webkit/tools/test_shell/image_decoder_unittest.cc
@@ -23,7 +23,7 @@ const int kFirstFrameIndex = 0;
 
 // Determine if we should test with file specified by |path| based
 // on |file_selection| and the |threshold| for the file size.
-bool ShouldSkipFile(const FilePath& path,
+bool ShouldSkipFile(const base::FilePath& path,
                     ImageDecoderTestFileSelection file_selection,
                     const int64 threshold) {
   if (file_selection == TEST_ALL)
@@ -36,21 +36,21 @@ bool ShouldSkipFile(const FilePath& path,
 
 }  // namespace
 
-void ReadFileToVector(const FilePath& path, std::vector<char>* contents) {
+void ReadFileToVector(const base::FilePath& path, std::vector<char>* contents) {
   std::string raw_image_data;
   file_util::ReadFileToString(path, &raw_image_data);
   contents->resize(raw_image_data.size());
   memcpy(&contents->at(0), raw_image_data.data(), raw_image_data.size());
 }
 
-FilePath GetMD5SumPath(const FilePath& path) {
-  static const FilePath::StringType kDecodedDataExtension(
+base::FilePath GetMD5SumPath(const base::FilePath& path) {
+  static const base::FilePath::StringType kDecodedDataExtension(
       FILE_PATH_LITERAL(".md5sum"));
-  return FilePath(path.value() + kDecodedDataExtension);
+  return base::FilePath(path.value() + kDecodedDataExtension);
 }
 
 #if defined(CALCULATE_MD5_SUMS)
-void SaveMD5Sum(const FilePath& path, const WebKit::WebImage& web_image) {
+void SaveMD5Sum(const base::FilePath& path, const WebKit::WebImage& web_image) {
   // Calculate MD5 sum.
   base::MD5Digest digest;
   web_image.getSkBitmap().lockPixels();
@@ -69,8 +69,8 @@ void SaveMD5Sum(const FilePath& path, const WebKit::WebImage& web_image) {
 
 #if !defined(CALCULATE_MD5_SUMS)
 void VerifyImage(const WebKit::WebImageDecoder& decoder,
-                 const FilePath& path,
-                 const FilePath& md5_sum_path,
+                 const base::FilePath& path,
+                 const base::FilePath& md5_sum_path,
                  size_t frame_index) {
   // Make sure decoding can complete successfully.
   EXPECT_TRUE(decoder.isSizeAvailable()) << path.value();
@@ -103,7 +103,7 @@ void VerifyImage(const WebKit::WebImageDecoder& decoder,
 #endif
 
 void ImageDecoderTest::SetUp() {
-  FilePath data_dir;
+  base::FilePath data_dir;
   ASSERT_TRUE(PathService::Get(base::DIR_SOURCE_ROOT, &data_dir));
   data_dir_ = data_dir.AppendASCII("webkit").
                        AppendASCII("data").
@@ -111,17 +111,17 @@ void ImageDecoderTest::SetUp() {
   ASSERT_TRUE(file_util::PathExists(data_dir_)) << data_dir_.value();
 }
 
-std::vector<FilePath> ImageDecoderTest::GetImageFiles() const {
+std::vector<base::FilePath> ImageDecoderTest::GetImageFiles() const {
   std::string pattern = "*." + format_;
 
   file_util::FileEnumerator enumerator(data_dir_,
                                        false,
                                        file_util::FileEnumerator::FILES);
 
-  std::vector<FilePath> image_files;
-  FilePath next_file_name;
+  std::vector<base::FilePath> image_files;
+  base::FilePath next_file_name;
   while (!(next_file_name = enumerator.Next()).empty()) {
-    FilePath base_name = next_file_name.BaseName();
+    base::FilePath base_name = next_file_name.BaseName();
 #if defined(OS_WIN)
     std::string base_name_ascii = WideToASCII(base_name.value());
 #else
@@ -135,8 +135,8 @@ std::vector<FilePath> ImageDecoderTest::GetImageFiles() const {
   return image_files;
 }
 
-bool ImageDecoderTest::ShouldImageFail(const FilePath& path) const {
-  static const FilePath::StringType kBadSuffix(FILE_PATH_LITERAL(".bad."));
+bool ImageDecoderTest::ShouldImageFail(const base::FilePath& path) const {
+  static const base::FilePath::StringType kBadSuffix(FILE_PATH_LITERAL(".bad."));
   return (path.value().length() > (kBadSuffix.length() + format_.length()) &&
           !path.value().compare(path.value().length() - format_.length() -
                                     kBadSuffix.length(),
@@ -146,18 +146,18 @@ bool ImageDecoderTest::ShouldImageFail(const FilePath& path) const {
 void ImageDecoderTest::TestDecoding(
     ImageDecoderTestFileSelection file_selection,
     const int64 threshold) {
-  const std::vector<FilePath> image_files(GetImageFiles());
-  for (std::vector<FilePath>::const_iterator i = image_files.begin();
+  const std::vector<base::FilePath> image_files(GetImageFiles());
+  for (std::vector<base::FilePath>::const_iterator i = image_files.begin();
        i != image_files.end(); ++i) {
     if (ShouldSkipFile(*i, file_selection, threshold))
       continue;
-    const FilePath md5_sum_path(GetMD5SumPath(*i));
+    const base::FilePath md5_sum_path(GetMD5SumPath(*i));
     TestWebKitImageDecoder(*i, md5_sum_path, kFirstFrameIndex);
   }
 }
 
-void  ImageDecoderTest::TestWebKitImageDecoder(const FilePath& image_path,
-  const FilePath& md5_sum_path, int desired_frame_index) const {
+void  ImageDecoderTest::TestWebKitImageDecoder(const base::FilePath& image_path,
+  const base::FilePath& md5_sum_path, int desired_frame_index) const {
   bool should_test_chunking = true;
   bool should_test_failed_images = true;
 #ifdef CALCULATE_MD5_SUMS
diff --git a/webkit/tools/test_shell/image_decoder_unittest.h b/webkit/tools/test_shell/image_decoder_unittest.h
index d9bff215a3be52..85b88c255caa73 100644
--- a/webkit/tools/test_shell/image_decoder_unittest.h
+++ b/webkit/tools/test_shell/image_decoder_unittest.h
@@ -37,7 +37,7 @@ enum ImageDecoderTestFileSelection {
 };
 
 // Returns the path the decoded data is saved at.
-FilePath GetMD5SumPath(const FilePath& path);
+base::FilePath GetMD5SumPath(const base::FilePath& path);
 
 class ImageDecoderTest : public testing::Test {
  public:
@@ -47,16 +47,16 @@ class ImageDecoderTest : public testing::Test {
   virtual void SetUp() OVERRIDE;
 
   // Returns the vector of image files for testing.
-  std::vector<FilePath> GetImageFiles() const;
+  std::vector<base::FilePath> GetImageFiles() const;
 
   // Returns true if the image is bogus and should not be successfully decoded.
-  bool ShouldImageFail(const FilePath& path) const;
+  bool ShouldImageFail(const base::FilePath& path) const;
 
   // Tests if decoder decodes image at image_path with underlying frame at
   // index desired_frame_index. The md5_sum_path is needed if the test is not
   // asked to generate one i.e. if # #define CALCULATE_MD5_SUMS is set.
-  void TestWebKitImageDecoder(const FilePath& image_path,
-    const FilePath& md5_sum_path, int desired_frame_index) const;
+  void TestWebKitImageDecoder(const base::FilePath& image_path,
+    const base::FilePath& md5_sum_path, int desired_frame_index) const;
 
   // Verifies each of the test image files is decoded correctly and matches the
   // expected state. |file_selection| and |threshold| can be used to select
@@ -77,7 +77,7 @@ class ImageDecoderTest : public testing::Test {
 
  protected:
   // Path to the test files.
-  FilePath data_dir_;
+  base::FilePath data_dir_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ImageDecoderTest);
diff --git a/webkit/tools/test_shell/plugin_tests.cc b/webkit/tools/test_shell/plugin_tests.cc
index 8a4dbdad681b54..ec352b46e8650e 100644
--- a/webkit/tools/test_shell/plugin_tests.cc
+++ b/webkit/tools/test_shell/plugin_tests.cc
@@ -42,7 +42,7 @@ const char kPluginsDir[] = "plugins";
 class PluginTest : public TestShellTest {
  public:
   PluginTest() {
-    FilePath executable_directory;
+    base::FilePath executable_directory;
     PathService::Get(base::DIR_EXE, &executable_directory);
     plugin_src_ = executable_directory.AppendASCII(TEST_PLUGIN_NAME);
     CHECK(file_util::PathExists(plugin_src_));
@@ -69,8 +69,8 @@ class PluginTest : public TestShellTest {
     TestShellTest::SetUp();
   }
 
-  FilePath plugin_src_;
-  FilePath plugin_file_path_;
+  base::FilePath plugin_src_;
+  base::FilePath plugin_file_path_;
 };
 
 // Tests navigator.plugins.refresh() works.
@@ -126,7 +126,7 @@ TEST_F(PluginTest, Refresh) {
 // Tests that if a frame is deleted as a result of calling NPP_HandleEvent, we
 // don't crash.
 TEST_F(PluginTest, DeleteFrameDuringEvent) {
-  FilePath test_html = data_dir_;
+  base::FilePath test_html = data_dir_;
   test_html = test_html.AppendASCII(kPluginsDir);
   test_html = test_html.AppendASCII("delete_frame.html");
   test_shell_->LoadFile(test_html);
@@ -144,7 +144,7 @@ TEST_F(PluginTest, DeleteFrameDuringEvent) {
 
 // Tests that a forced reload of the plugin will not crash.
 TEST_F(PluginTest, ForceReload) {
-  FilePath test_html = data_dir_;
+  base::FilePath test_html = data_dir_;
   test_html = test_html.AppendASCII(kPluginsDir);
   test_html = test_html.AppendASCII("force_reload.html");
   test_shell_->LoadFile(test_html);
@@ -174,7 +174,7 @@ BOOL CALLBACK EnumChildProc(HWND hwnd, LPARAM lparam) {
 #endif
 
 TEST_F(PluginTest, MAYBE_PluginVisibilty) {
-  FilePath test_html = data_dir_;
+  base::FilePath test_html = data_dir_;
   test_html = test_html.AppendASCII(kPluginsDir);
   test_html = test_html.AppendASCII("plugin_visibility.html");
   test_shell_->LoadFile(test_html);
diff --git a/webkit/tools/test_shell/run_all_tests.cc b/webkit/tools/test_shell/run_all_tests.cc
index 19d1a30bba9043..9b3ec4670fa67d 100644
--- a/webkit/tools/test_shell/run_all_tests.cc
+++ b/webkit/tools/test_shell/run_all_tests.cc
@@ -43,7 +43,7 @@ class TestShellTestSuite : public base::TestSuite {
   virtual void Initialize() {
     // Override DIR_EXE early in case anything in base::TestSuite uses it.
 #if defined(OS_MACOSX)
-    FilePath path;
+    base::FilePath path;
     PathService::Get(base::DIR_EXE, &path);
     path = path.AppendASCII("TestShell.app");
     base::mac::SetOverrideFrameworkBundlePath(path);
diff --git a/webkit/tools/test_shell/simple_appcache_system.cc b/webkit/tools/test_shell/simple_appcache_system.cc
index 6c066db8bdd5c8..8503672e60678d 100644
--- a/webkit/tools/test_shell/simple_appcache_system.cc
+++ b/webkit/tools/test_shell/simple_appcache_system.cc
@@ -387,7 +387,7 @@ SimpleAppCacheSystem::~SimpleAppCacheSystem() {
   }
 }
 
-void SimpleAppCacheSystem::InitOnUIThread(const FilePath& cache_directory) {
+void SimpleAppCacheSystem::InitOnUIThread(const base::FilePath& cache_directory) {
   DCHECK(!ui_message_loop_);
   ui_message_loop_ = MessageLoop::current();
   cache_directory_ = cache_directory;
diff --git a/webkit/tools/test_shell/simple_appcache_system.h b/webkit/tools/test_shell/simple_appcache_system.h
index 2975268ae02e6d..73719137b4a174 100644
--- a/webkit/tools/test_shell/simple_appcache_system.h
+++ b/webkit/tools/test_shell/simple_appcache_system.h
@@ -38,7 +38,7 @@ class SimpleAppCacheSystem {
   virtual ~SimpleAppCacheSystem();
 
   // One-time main UI thread initialization.
-  static void InitializeOnUIThread(const FilePath& cache_directory) {
+  static void InitializeOnUIThread(const base::FilePath& cache_directory) {
     if (instance_)
       instance_->InitOnUIThread(cache_directory);
   }
@@ -85,7 +85,7 @@ class SimpleAppCacheSystem {
   friend class SimpleFrontendProxy;
 
   // Instance methods called by our static public methods
-  void InitOnUIThread(const FilePath& cache_directory);
+  void InitOnUIThread(const base::FilePath& cache_directory);
   void InitOnIOThread(net::URLRequestContext* request_context);
   void CleanupIOThread();
   WebKit::WebApplicationCacheHost* CreateCacheHostForWebKit(
@@ -109,7 +109,7 @@ class SimpleAppCacheSystem {
     return ui_message_loop_ ? true : false;
   }
 
-  FilePath cache_directory_;
+  base::FilePath cache_directory_;
   MessageLoop* io_message_loop_;
   MessageLoop* ui_message_loop_;
   scoped_refptr<SimpleBackendProxy> backend_proxy_;
diff --git a/webkit/tools/test_shell/simple_file_system.cc b/webkit/tools/test_shell/simple_file_system.cc
index f66554137d1667..87aabf448d4505 100644
--- a/webkit/tools/test_shell/simple_file_system.cc
+++ b/webkit/tools/test_shell/simple_file_system.cc
@@ -54,10 +54,10 @@ namespace {
 MessageLoop* g_io_thread;
 webkit_blob::BlobStorageController* g_blob_storage_controller;
 
-void RegisterBlob(const GURL& blob_url, const FilePath& file_path) {
+void RegisterBlob(const GURL& blob_url, const base::FilePath& file_path) {
   DCHECK(g_blob_storage_controller);
 
-  FilePath::StringType extension = file_path.Extension();
+  base::FilePath::StringType extension = file_path.Extension();
   if (!extension.empty())
     extension = extension.substr(1);  // Strip leading ".".
 
@@ -324,7 +324,7 @@ void SimpleFileSystem::DidFinish(WebFileSystemCallbacks* callbacks,
 void SimpleFileSystem::DidGetMetadata(WebFileSystemCallbacks* callbacks,
                                       base::PlatformFileError result,
                                       const base::PlatformFileInfo& info,
-                                      const FilePath& platform_path) {
+                                      const base::FilePath& platform_path) {
   if (result == base::PLATFORM_FILE_OK) {
     WebFileInfo web_file_info;
     web_file_info.length = info.size;
@@ -388,7 +388,7 @@ void SimpleFileSystem::DidCreateSnapshotFile(
     WebFileSystemCallbacks* callbacks,
     base::PlatformFileError result,
     const base::PlatformFileInfo& info,
-    const FilePath& platform_path,
+    const base::FilePath& platform_path,
     const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref) {
   DCHECK(g_io_thread);
   if (result == base::PLATFORM_FILE_OK) {
diff --git a/webkit/tools/test_shell/simple_file_system.h b/webkit/tools/test_shell/simple_file_system.h
index 7d55a9f7dbf52e..099aebaaff4221 100644
--- a/webkit/tools/test_shell/simple_file_system.h
+++ b/webkit/tools/test_shell/simple_file_system.h
@@ -128,7 +128,7 @@ class SimpleFileSystem
   void DidGetMetadata(WebKit::WebFileSystemCallbacks* callbacks,
                       base::PlatformFileError result,
                       const base::PlatformFileInfo& info,
-                      const FilePath& platform_path);
+                      const base::FilePath& platform_path);
   void DidReadDirectory(
       WebKit::WebFileSystemCallbacks* callbacks,
       base::PlatformFileError result,
@@ -144,7 +144,7 @@ class SimpleFileSystem
       WebKit::WebFileSystemCallbacks* callbacks,
       base::PlatformFileError result,
       const base::PlatformFileInfo& info,
-      const FilePath& platform_path,
+      const base::FilePath& platform_path,
       const scoped_refptr<webkit_blob::ShareableFileReference>& file_ref);
 
   // A temporary directory for FileSystem API.
diff --git a/webkit/tools/test_shell/simple_resource_loader_bridge.cc b/webkit/tools/test_shell/simple_resource_loader_bridge.cc
index 02aaf802313aa0..743ba26bf38952 100644
--- a/webkit/tools/test_shell/simple_resource_loader_bridge.cc
+++ b/webkit/tools/test_shell/simple_resource_loader_bridge.cc
@@ -93,14 +93,14 @@ namespace {
 
 struct TestShellRequestContextParams {
   TestShellRequestContextParams(
-      const FilePath& in_cache_path,
+      const base::FilePath& in_cache_path,
       net::HttpCache::Mode in_cache_mode,
       bool in_no_proxy)
       : cache_path(in_cache_path),
         cache_mode(in_cache_mode),
         no_proxy(in_no_proxy) {}
 
-  FilePath cache_path;
+  base::FilePath cache_path;
   net::HttpCache::Mode cache_mode;
   bool no_proxy;
 };
@@ -177,7 +177,7 @@ class TestShellNetworkDelegate : public net::NetworkDelegate {
     return rv == net::OK;
   }
   virtual bool OnCanAccessFile(const net::URLRequest& request,
-                               const FilePath& path) const OVERRIDE {
+                               const base::FilePath& path) const OVERRIDE {
     return true;
   }
   virtual bool OnCanThrottleRequest(
@@ -475,7 +475,7 @@ class RequestProxy
 
     download_to_file_ = params->download_to_file;
     if (download_to_file_) {
-      FilePath path;
+      base::FilePath path;
       if (file_util::CreateTemporaryFile(&path)) {
         downloaded_file_ = ShareableFileReference::GetOrCreate(
             path, ShareableFileReference::DELETE_ON_FINAL_RELEASE,
@@ -755,7 +755,7 @@ class RequestProxy
     // Get the File URL.
     original_request.replace(0, http_prefix.size(), file_url_prefix_);
 
-    FilePath file_path;
+    base::FilePath file_path;
     if (!net::FileURLToFilePath(GURL(original_request), &file_path)) {
       NOTREACHED();
     }
@@ -1027,7 +1027,7 @@ class CookieGetter : public base::RefCountedThreadSafe<CookieGetter> {
 
 // static
 void SimpleResourceLoaderBridge::Init(
-    const FilePath& cache_path,
+    const base::FilePath& cache_path,
     net::HttpCache::Mode cache_mode,
     bool no_proxy) {
   // Make sure to stop any existing IO thread since it may be using the
diff --git a/webkit/tools/test_shell/simple_resource_loader_bridge.h b/webkit/tools/test_shell/simple_resource_loader_bridge.h
index 6d1c63a6faddd0..35d38b5e58e75f 100644
--- a/webkit/tools/test_shell/simple_resource_loader_bridge.h
+++ b/webkit/tools/test_shell/simple_resource_loader_bridge.h
@@ -10,9 +10,12 @@
 #include "net/http/http_cache.h"
 #include "webkit/glue/resource_loader_bridge.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 class SimpleResourceLoaderBridge {
  public:
   // Call this function to initialize the simple resource loader bridge.
@@ -21,7 +24,7 @@ class SimpleResourceLoaderBridge {
   // NOTE: If this function is not called, then a default request context will
   // be initialized lazily.
   //
-  static void Init(const FilePath& cache_path,
+  static void Init(const base::FilePath& cache_path,
                    net::HttpCache::Mode cache_mode,
                    bool no_proxy);
 
diff --git a/webkit/tools/test_shell/test_shell.cc b/webkit/tools/test_shell/test_shell.cc
index 763495ea41c269..677dc426f9e173 100644
--- a/webkit/tools/test_shell/test_shell.cc
+++ b/webkit/tools/test_shell/test_shell.cc
@@ -88,7 +88,7 @@ class URLRequestTestShellFileJob : public net::URLRequestFileJob {
       net::URLRequest* request,
       net::NetworkDelegate* network_delegate,
       const std::string& scheme) {
-    FilePath path;
+    base::FilePath path;
     PathService::Get(base::DIR_EXE, &path);
     path = path.AppendASCII("resources");
     path = path.AppendASCII("inspector");
@@ -99,7 +99,7 @@ class URLRequestTestShellFileJob : public net::URLRequestFileJob {
  private:
   URLRequestTestShellFileJob(net::URLRequest* request,
                              net::NetworkDelegate* network_delegate,
-                             const FilePath& path)
+                             const base::FilePath& path)
       : net::URLRequestFileJob(request, network_delegate, path) {
   }
   virtual ~URLRequestTestShellFileJob() { }
@@ -263,7 +263,7 @@ void TestShell::InitLogging(bool suppress_error_dialogs,
       destination = logging::LOG_ONLY_TO_FILE;
 
     // We might have multiple test_shell processes going at once
-    FilePath log_filename;
+    base::FilePath log_filename;
     PathService::Get(base::DIR_EXE, &log_filename);
     log_filename = log_filename.AppendASCII("test_shell.log");
     logging::InitLogging(
@@ -459,9 +459,9 @@ WebView* TestShell::CreateWebView() {
 
 void TestShell::ShowDevTools() {
   if (!devtools_shell_) {
-    FilePath dir_exe;
+    base::FilePath dir_exe;
     PathService::Get(base::DIR_EXE, &dir_exe);
-    FilePath devtools_path =
+    base::FilePath devtools_path =
         dir_exe.AppendASCII("resources/inspector/devtools.html");
     TestShell* devtools_shell;
     TestShell::CreateNewWindow(GURL(devtools_path.value()),
@@ -502,7 +502,7 @@ void TestShell::ResetTestController() {
     geolocation_client_mock_->resetMock();
 }
 
-void TestShell::LoadFile(const FilePath& file) {
+void TestShell::LoadFile(const base::FilePath& file) {
   LoadURLForFrame(net::FilePathToFileURL(file), string16());
 }
 
@@ -559,7 +559,7 @@ void TestShell::GoBackOrForward(int offset) {
 }
 
 void TestShell::DumpDocumentText() {
-  FilePath file_path;
+  base::FilePath file_path;
   if (!PromptForSaveFile(L"Dump document text", &file_path))
       return;
 
@@ -569,7 +569,7 @@ void TestShell::DumpDocumentText() {
 }
 
 void TestShell::DumpRenderTree() {
-  FilePath file_path;
+  base::FilePath file_path;
   if (!PromptForSaveFile(L"Dump render tree", &file_path))
     return;
 
diff --git a/webkit/tools/test_shell/test_shell.h b/webkit/tools/test_shell/test_shell.h
index 58118ab6fa80ec..e464423f68a96c 100644
--- a/webkit/tools/test_shell/test_shell.h
+++ b/webkit/tools/test_shell/test_shell.h
@@ -59,7 +59,7 @@ class TestShell : public base::SupportsWeakPtr<TestShell>  {
       bool dump_pixels;
 
       // Filename we dump pixels to (when pixel testing is enabled).
-      FilePath pixel_file_name;
+      base::FilePath pixel_file_name;
       // The md5 hash of the bitmap dump (when pixel testing is enabled).
       std::string pixel_hash;
       // URL of the test.
@@ -150,14 +150,14 @@ class TestShell : public base::SupportsWeakPtr<TestShell>  {
       return true;
     }
 
-    void LoadFile(const FilePath& file);
+    void LoadFile(const base::FilePath& file);
     void LoadURL(const GURL& url);
     void LoadURLForFrame(const GURL& url, const string16& frame_name);
     void GoBackOrForward(int offset);
     void Reload();
     bool Navigate(const TestNavigationEntry& entry, bool reload);
 
-    bool PromptForSaveFile(const wchar_t* prompt_title, FilePath* result);
+    bool PromptForSaveFile(const wchar_t* prompt_title, base::FilePath* result);
     string16 GetDocumentText();
     void DumpDocumentText();
     void DumpRenderTree();
diff --git a/webkit/tools/test_shell/test_shell_gtk.cc b/webkit/tools/test_shell/test_shell_gtk.cc
index 0ec3fd5073688b..6576d07b446772 100644
--- a/webkit/tools/test_shell/test_shell_gtk.cc
+++ b/webkit/tools/test_shell/test_shell_gtk.cc
@@ -41,9 +41,9 @@ using WebKit::WebWidget;
 
 namespace {
 
-// Convert a FilePath into an FcChar* (used by fontconfig).
+// Convert a base::FilePath into an FcChar* (used by fontconfig).
 // The pointer only lives for the duration for the expression.
-const FcChar8* FilePathAsFcChar(const FilePath& path) {
+const FcChar8* FilePathAsFcChar(const base::FilePath& path) {
   return reinterpret_cast<const FcChar8*>(path.value().c_str());
 }
 
@@ -159,12 +159,12 @@ void TestShell::InitializeTestShell(bool layout_test_mode,
 
   web_prefs_ = new webkit_glue::WebPreferences;
 
-  FilePath data_path;
+  base::FilePath data_path;
   PathService::Get(base::DIR_EXE, &data_path);
   data_path = data_path.Append("test_shell.pak");
   ResourceBundle::InitSharedInstanceWithPakPath(data_path);
 
-  FilePath resources_dir;
+  base::FilePath resources_dir;
   PathService::Get(base::DIR_SOURCE_ROOT, &resources_dir);
   resources_dir = resources_dir.Append("webkit/tools/test_shell/resources");
 
@@ -185,7 +185,7 @@ void TestShell::InitializeTestShell(bool layout_test_mode,
     FcInit();
 
     FcConfig* fontcfg = FcConfigCreate();
-    FilePath fontconfig_path = resources_dir.Append("fonts.conf");
+    base::FilePath fontconfig_path = resources_dir.Append("fonts.conf");
     if (!FcConfigParseAndLoad(fontcfg, FilePathAsFcChar(fontconfig_path),
                               true)) {
       LOG(FATAL) << "Failed to parse fontconfig config file";
@@ -263,7 +263,7 @@ void TestShell::InitializeTestShell(bool layout_test_mode,
     }
 
     // Also load the layout-test-specific "Ahem" font.
-    FilePath ahem_path = resources_dir.Append("AHEM____.TTF");
+    base::FilePath ahem_path = resources_dir.Append("AHEM____.TTF");
     if (!FcConfigAppFontAddFile(fontcfg, FilePathAsFcChar(ahem_path))) {
       LOG(FATAL) << "Failed to load font " << ahem_path.value().c_str();
     }
@@ -508,7 +508,7 @@ void TestShell::LoadURLForFrame(const GURL& url,
 }
 
 bool TestShell::PromptForSaveFile(const wchar_t* prompt_title,
-                                  FilePath* result) {
+                                  base::FilePath* result) {
   GtkWidget* dialog;
   dialog = gtk_file_chooser_dialog_new(WideToUTF8(prompt_title).c_str(),
                                        GTK_WINDOW(m_mainWnd),
@@ -525,7 +525,7 @@ bool TestShell::PromptForSaveFile(const wchar_t* prompt_title,
   }
   char* path = gtk_file_chooser_get_filename(GTK_FILE_CHOOSER(dialog));
   gtk_widget_destroy(dialog);
-  *result = FilePath(path);
+  *result = base::FilePath(path);
   g_free(path);
   return true;
 }
@@ -538,7 +538,7 @@ std::string TestShell::RewriteLocalUrl(const std::string& url) {
 
   std::string new_url(url);
   if (url.compare(0, kPrefixLen, kPrefix, kPrefixLen) == 0) {
-    FilePath replace_path;
+    base::FilePath replace_path;
     PathService::Get(base::DIR_SOURCE_ROOT, &replace_path);
     replace_path = replace_path.Append(
         "third_party/WebKit/LayoutTests/");
diff --git a/webkit/tools/test_shell/test_shell_mac.mm b/webkit/tools/test_shell/test_shell_mac.mm
index ccfaa670aa3a4e..fe86310f0e00cc 100644
--- a/webkit/tools/test_shell/test_shell_mac.mm
+++ b/webkit/tools/test_shell/test_shell_mac.mm
@@ -78,12 +78,12 @@
     TestShell::window_map_ = LAZY_INSTANCE_INITIALIZER;
 
 // Helper method for getting the path to the test shell resources directory.
-FilePath GetResourcesFilePath() {
-  FilePath path;
+base::FilePath GetResourcesFilePath() {
+  base::FilePath path;
   // We need to know if we're bundled or not to know which path to use.
   if (base::mac::AmIBundled()) {
     PathService::Get(base::DIR_EXE, &path);
-    path = path.Append(FilePath::kParentDirectory);
+    path = path.Append(base::FilePath::kParentDirectory);
     return path.AppendASCII("Resources");
   } else {
     PathService::Get(base::DIR_SOURCE_ROOT, &path);
@@ -215,7 +215,7 @@ - (void)cleanup:(id)window {
   NSString *resource_path =
       [base::mac::FrameworkBundle() pathForResource:@"test_shell"
                                              ofType:@"pak"];
-  FilePath resources_pak_path([resource_path fileSystemRepresentation]);
+  base::FilePath resources_pak_path([resource_path fileSystemRepresentation]);
   if (!g_resource_data_pack->LoadFromPath(resources_pak_path)) {
     LOG(FATAL) << "failed to load test_shell.pak";
   }
@@ -236,7 +236,7 @@ - (void)cleanup:(id)window {
 
   // Add <app bundle's parent dir>/plugins to the plugin path so we can load
   // test plugins.
-  FilePath plugins_dir;
+  base::FilePath plugins_dir;
   PathService::Get(base::DIR_EXE, &plugins_dir);
   if (base::mac::AmIBundled()) {
     plugins_dir = plugins_dir.AppendASCII("../../../plugins");
@@ -539,7 +539,7 @@ - (void)run:(id)ignore {
 }
 
 bool TestShell::PromptForSaveFile(const wchar_t* prompt_title,
-                                  FilePath* result)
+                                  base::FilePath* result)
 {
   NSSavePanel* save_panel = [NSSavePanel savePanel];
 
@@ -552,7 +552,7 @@ - (void)run:(id)ignore {
   [save_panel setDirectoryURL:[NSURL fileURLWithPath:NSHomeDirectory()]];
   [save_panel setNameFieldStringValue:@""];
   if ([save_panel runModal] == NSFileHandlingPanelOKButton) {
-    *result = FilePath([[[save_panel URL] path] fileSystemRepresentation]);
+    *result = base::FilePath([[[save_panel URL] path] fileSystemRepresentation]);
     return true;
   }
   return false;
@@ -566,7 +566,7 @@ - (void)run:(id)ignore {
 
   std::string new_url(url);
   if (url.compare(0, kPrefixLen, kPrefix, kPrefixLen) == 0) {
-    FilePath replace_path;
+    base::FilePath replace_path;
     PathService::Get(base::DIR_SOURCE_ROOT, &replace_path);
     replace_path = replace_path.Append(
         "third_party/WebKit/LayoutTests/");
@@ -628,7 +628,7 @@ - (void)run:(id)ignore {
     // Use webkit's broken image icon (16x16)
     static std::string broken_image_data;
     if (broken_image_data.empty()) {
-      FilePath path = GetResourcesFilePath();
+      base::FilePath path = GetResourcesFilePath();
       // In order to match WebKit's colors for the missing image, we have to
       // use a PNG. The GIF doesn't have the color range needed to correctly
       // match the TIFF they use in Safari.
@@ -644,7 +644,7 @@ - (void)run:(id)ignore {
     // Use webkit's text area resizer image.
     static std::string resize_corner_data;
     if (resize_corner_data.empty()) {
-      FilePath path = GetResourcesFilePath();
+      base::FilePath path = GetResourcesFilePath();
       path = path.AppendASCII("textAreaResizeCorner.png");
       bool success = file_util::ReadFileToString(path, &resize_corner_data);
       if (!success) {
diff --git a/webkit/tools/test_shell/test_shell_main.cc b/webkit/tools/test_shell/test_shell_main.cc
index 5bebaad72c1770..5c98d985a9e4a8 100644
--- a/webkit/tools/test_shell/test_shell_main.cc
+++ b/webkit/tools/test_shell/test_shell_main.cc
@@ -160,7 +160,7 @@ int main(int argc, char* argv[]) {
   if (parsed_command_line.HasSwitch(test_shell::kEnableFileCookies))
     net::CookieMonster::EnableFileScheme();
 
-  FilePath cache_path =
+  base::FilePath cache_path =
       parsed_command_line.GetSwitchValuePath(test_shell::kCacheDir);
   if (cache_path.empty()) {
     PathService::Get(base::DIR_EXE, &cache_path);
@@ -214,7 +214,7 @@ int main(int argc, char* argv[]) {
   // Treat the first argument as the initial URL to open.
   GURL starting_url;
 
-  FilePath path;
+  base::FilePath path;
   PathService::Get(base::DIR_SOURCE_ROOT, &path);
   path = path.AppendASCII("webkit").AppendASCII("data")
              .AppendASCII("test_shell").AppendASCII("index.html");
@@ -227,7 +227,7 @@ int main(int argc, char* argv[]) {
       starting_url = url;
     } else {
       // Treat as a relative file path.
-      FilePath path = FilePath(args[0]);
+      base::FilePath path = base::FilePath(args[0]);
       file_util::AbsolutePath(&path);
       starting_url = net::FilePathToFileURL(path);
     }
diff --git a/webkit/tools/test_shell/test_shell_request_context.cc b/webkit/tools/test_shell/test_shell_request_context.cc
index 5bdf4c954e30ae..eec8e8235b3808 100644
--- a/webkit/tools/test_shell/test_shell_request_context.cc
+++ b/webkit/tools/test_shell/test_shell_request_context.cc
@@ -58,11 +58,11 @@ class TestShellHttpUserAgentSettings : public net::HttpUserAgentSettings {
 
 TestShellRequestContext::TestShellRequestContext()
     : ALLOW_THIS_IN_INITIALIZER_LIST(storage_(this)) {
-  Init(FilePath(), net::HttpCache::NORMAL, false);
+  Init(base::FilePath(), net::HttpCache::NORMAL, false);
 }
 
 TestShellRequestContext::TestShellRequestContext(
-    const FilePath& cache_path,
+    const base::FilePath& cache_path,
     net::HttpCache::Mode cache_mode,
     bool no_proxy)
     : ALLOW_THIS_IN_INITIALIZER_LIST(storage_(this)) {
@@ -70,7 +70,7 @@ TestShellRequestContext::TestShellRequestContext(
 }
 
 void TestShellRequestContext::Init(
-    const FilePath& cache_path,
+    const base::FilePath& cache_path,
     net::HttpCache::Mode cache_mode,
     bool no_proxy) {
   storage_.set_cookie_store(new net::CookieMonster(NULL, NULL));
diff --git a/webkit/tools/test_shell/test_shell_request_context.h b/webkit/tools/test_shell/test_shell_request_context.h
index 27ef6fedacd399..bcd59e41eb4cd9 100644
--- a/webkit/tools/test_shell/test_shell_request_context.h
+++ b/webkit/tools/test_shell/test_shell_request_context.h
@@ -10,7 +10,9 @@
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_storage.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace fileapi {
 class FileSystemContext;
@@ -28,7 +30,7 @@ class TestShellRequestContext : public net::URLRequestContext {
 
   // Use an on-disk cache at the specified location.  Optionally, use the cache
   // in playback or record mode.
-  TestShellRequestContext(const FilePath& cache_path,
+  TestShellRequestContext(const base::FilePath& cache_path,
                           net::HttpCache::Mode cache_mode,
                           bool no_proxy);
 
@@ -43,7 +45,7 @@ class TestShellRequestContext : public net::URLRequestContext {
   }
 
  private:
-  void Init(const FilePath& cache_path, net::HttpCache::Mode cache_mode,
+  void Init(const base::FilePath& cache_path, net::HttpCache::Mode cache_mode,
             bool no_proxy);
 
   net::URLRequestContextStorage storage_;
diff --git a/webkit/tools/test_shell/test_shell_test.cc b/webkit/tools/test_shell/test_shell_test.cc
index 16357f2127d3f6..2ea5e743f6ae4a 100644
--- a/webkit/tools/test_shell/test_shell_test.cc
+++ b/webkit/tools/test_shell/test_shell_test.cc
@@ -17,7 +17,7 @@
 #include "webkit/user_agent/user_agent.h"
 #include "webkit/user_agent/user_agent_util.h"
 
-GURL TestShellTest::GetTestURL(const FilePath& test_case_path,
+GURL TestShellTest::GetTestURL(const base::FilePath& test_case_path,
                                const std::string& test_case) {
   return net::FilePathToFileURL(test_case_path.AppendASCII(test_case));
 }
diff --git a/webkit/tools/test_shell/test_shell_test.h b/webkit/tools/test_shell/test_shell_test.h
index 3e2e354144c4c2..c29a37d5c696fc 100644
--- a/webkit/tools/test_shell/test_shell_test.h
+++ b/webkit/tools/test_shell/test_shell_test.h
@@ -20,7 +20,7 @@
 class TestShellTest : public testing::Test {
  protected:
   // Returns the path "test_case_path/test_case".
-  GURL GetTestURL(const FilePath& test_case_path,
+  GURL GetTestURL(const base::FilePath& test_case_path,
                   const std::string& test_case);
 
   virtual void SetUp() OVERRIDE;
@@ -31,7 +31,7 @@ class TestShellTest : public testing::Test {
 
  protected:
   // Location of SOURCE_ROOT/webkit/data/
-  FilePath data_dir_;
+  base::FilePath data_dir_;
 
   TestShell* test_shell_;
 };
diff --git a/webkit/tools/test_shell/test_shell_webkit_init.cc b/webkit/tools/test_shell/test_shell_webkit_init.cc
index ded88b374118b3..72ddbbf5e0ea7c 100644
--- a/webkit/tools/test_shell/test_shell_webkit_init.cc
+++ b/webkit/tools/test_shell/test_shell_webkit_init.cc
@@ -52,7 +52,7 @@ TestShellWebKitInit::TestShellWebKitInit(bool layout_test_mode)
   WebKit::WebRuntimeFeatures::enableJavaScriptI18NAPI(true);
 
   // Load libraries for media and enable the media player.
-  FilePath module_path;
+  base::FilePath module_path;
   WebKit::WebRuntimeFeatures::enableMediaPlayer(
       PathService::Get(base::DIR_MODULE, &module_path) &&
       media::InitializeMediaLibrary(module_path));
@@ -277,7 +277,7 @@ void TestShellWebKitInit::GetPlugins(
   webkit::npapi::PluginList::Singleton()->GetPlugins(plugins);
   // Don't load the forked TestNetscapePlugIn in the chromium code, use
   // the copy in webkit.org's repository instead.
-  const FilePath::StringType kPluginBlackList[] = {
+  const base::FilePath::StringType kPluginBlackList[] = {
     FILE_PATH_LITERAL("npapi_layout_test_plugin.dll"),
     FILE_PATH_LITERAL("WebKitTestNetscapePlugIn.plugin"),
     FILE_PATH_LITERAL("libnpapi_layout_test_plugin.so"),
@@ -285,7 +285,7 @@ void TestShellWebKitInit::GetPlugins(
   for (int i = plugins->size() - 1; i >= 0; --i) {
     webkit::WebPluginInfo plugin_info = plugins->at(i);
     for (size_t j = 0; j < arraysize(kPluginBlackList); ++j) {
-      if (plugin_info.path.BaseName() == FilePath(kPluginBlackList[j])) {
+      if (plugin_info.path.BaseName() == base::FilePath(kPluginBlackList[j])) {
         plugins->erase(plugins->begin() + i);
       }
     }
diff --git a/webkit/tools/test_shell/test_shell_win.cc b/webkit/tools/test_shell/test_shell_win.cc
index b2d2c465de7d93..0897c44b92c44d 100644
--- a/webkit/tools/test_shell/test_shell_win.cc
+++ b/webkit/tools/test_shell/test_shell_win.cc
@@ -101,13 +101,13 @@ bool MinidumpCallback(const wchar_t *dumpPath,
   // will be happening on developers' machines where they have debuggers.
   base::StackString16<kPathBufSize * 2> origPath;
   origPath->append(dumpPath);
-  origPath->push_back(FilePath::kSeparators[0]);
+  origPath->push_back(base::FilePath::kSeparators[0]);
   origPath->append(minidumpID);
   origPath->append(L".dmp");
 
   base::StackString16<kPathBufSize * 2> newPath;
   newPath->append(dumpPath);
-  newPath->push_back(FilePath::kSeparators[0]);
+  newPath->push_back(base::FilePath::kSeparators[0]);
   newPath->append(g_currentTestName);
   newPath->append(L"-");
   newPath->append(minidumpID);
@@ -121,8 +121,8 @@ bool MinidumpCallback(const wchar_t *dumpPath,
 }
 
 // Helper method for getting the path to the test shell resources directory.
-FilePath GetResourcesFilePath() {
-  FilePath path;
+base::FilePath GetResourcesFilePath() {
+  base::FilePath path;
   PathService::Get(base::DIR_SOURCE_ROOT, &path);
   path = path.AppendASCII("webkit");
   path = path.AppendASCII("tools");
@@ -251,7 +251,7 @@ std::string TestShell::RewriteLocalUrl(const std::string& url) {
 
   std::string new_url(url);
   if (url.compare(0, kPrefixLen, kPrefix, kPrefixLen) == 0) {
-    FilePath replace_url;
+    base::FilePath replace_url;
     PathService::Get(base::DIR_EXE, &replace_url);
     replace_url = replace_url.DirName();
     replace_url = replace_url.DirName();
@@ -640,7 +640,7 @@ INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam) {
 }
 
 bool TestShell::PromptForSaveFile(const wchar_t* prompt_title,
-                                  FilePath* result) {
+                                  base::FilePath* result) {
   wchar_t path_buf[MAX_PATH] = L"data.txt";
 
   OPENFILENAME info = {0};
@@ -654,7 +654,7 @@ bool TestShell::PromptForSaveFile(const wchar_t* prompt_title,
   if (!GetSaveFileName(&info))
     return false;
 
-  *result = FilePath(info.lpstrFile);
+  *result = base::FilePath(info.lpstrFile);
   return true;
 }
 
@@ -689,7 +689,7 @@ base::StringPiece TestShellWebKitInit::GetDataResource(
     // Use webkit's broken image icon (16x16)
     static std::string broken_image_data;
     if (broken_image_data.empty()) {
-      FilePath path = GetResourcesFilePath();
+      base::FilePath path = GetResourcesFilePath();
       path = path.AppendASCII("missingImage.gif");
       bool success = file_util::ReadFileToString(path, &broken_image_data);
       if (!success) {
@@ -702,7 +702,7 @@ base::StringPiece TestShellWebKitInit::GetDataResource(
     // Use webkit's text area resizer image.
     static std::string resize_corner_data;
     if (resize_corner_data.empty()) {
-      FilePath path = GetResourcesFilePath();
+      base::FilePath path = GetResourcesFilePath();
       path = path.AppendASCII("textAreaResizeCorner.png");
       bool success = file_util::ReadFileToString(path, &resize_corner_data);
       if (!success) {
diff --git a/webkit/tools/test_shell/test_webview_delegate.cc b/webkit/tools/test_shell/test_webview_delegate.cc
index e9462552e8f545..1fb12e08946e22 100644
--- a/webkit/tools/test_shell/test_webview_delegate.cc
+++ b/webkit/tools/test_shell/test_webview_delegate.cc
@@ -823,7 +823,7 @@ void TestWebViewDelegate::openFileSystem(
 // WebPluginPageDelegate -----------------------------------------------------
 
 WebKit::WebPlugin* TestWebViewDelegate::CreatePluginReplacement(
-    const FilePath& file_path) {
+    const base::FilePath& file_path) {
   return NULL;
 }
 
diff --git a/webkit/tools/test_shell/test_webview_delegate.h b/webkit/tools/test_shell/test_webview_delegate.h
index be1464ddff0fb2..e882017db8b415 100644
--- a/webkit/tools/test_shell/test_webview_delegate.h
+++ b/webkit/tools/test_shell/test_webview_delegate.h
@@ -236,10 +236,10 @@ class TestWebViewDelegate : public WebKit::WebViewClient,
 
   // webkit::npapi::WebPluginPageDelegate
   virtual webkit::npapi::WebPluginDelegate* CreatePluginDelegate(
-      const FilePath& url,
+      const base::FilePath& url,
       const std::string& mime_type) OVERRIDE;
   virtual WebKit::WebPlugin* CreatePluginReplacement(
-      const FilePath& file_path) OVERRIDE;
+      const base::FilePath& file_path) OVERRIDE;
   virtual void CreatedPluginWindow(
       gfx::PluginWindowHandle handle) OVERRIDE;
   virtual void WillDestroyPluginWindow(
diff --git a/webkit/tools/test_shell/test_webview_delegate_gtk.cc b/webkit/tools/test_shell/test_webview_delegate_gtk.cc
index 8141b1ca6bface..ec729308c677e1 100644
--- a/webkit/tools/test_shell/test_webview_delegate_gtk.cc
+++ b/webkit/tools/test_shell/test_webview_delegate_gtk.cc
@@ -198,7 +198,7 @@ void TestWebViewDelegate::runModal() {
 // WebPluginPageDelegate ------------------------------------------------------
 
 webkit::npapi::WebPluginDelegate* TestWebViewDelegate::CreatePluginDelegate(
-    const FilePath& path,
+    const base::FilePath& path,
     const std::string& mime_type) {
   return webkit::npapi::WebPluginDelegateImpl::Create(path, mime_type);
 }
diff --git a/webkit/tools/test_shell/test_webview_delegate_mac.mm b/webkit/tools/test_shell/test_webview_delegate_mac.mm
index 197ad970e4db39..42f5a64c725308 100644
--- a/webkit/tools/test_shell/test_webview_delegate_mac.mm
+++ b/webkit/tools/test_shell/test_webview_delegate_mac.mm
@@ -227,7 +227,7 @@ - (NSRect)_growBoxRect;
 // WebPluginPageDelegate ------------------------------------------------------
 
 webkit::npapi::WebPluginDelegate* TestWebViewDelegate::CreatePluginDelegate(
-    const FilePath& path,
+    const base::FilePath& path,
     const std::string& mime_type) {
   WebWidgetHost *host = GetWidgetHost();
   if (!host)
diff --git a/webkit/tools/test_shell/test_webview_delegate_win.cc b/webkit/tools/test_shell/test_webview_delegate_win.cc
index f9ea1a72ad30a5..c811f0ead99a09 100644
--- a/webkit/tools/test_shell/test_webview_delegate_win.cc
+++ b/webkit/tools/test_shell/test_webview_delegate_win.cc
@@ -133,7 +133,7 @@ void TestWebViewDelegate::runModal() {
 // WebPluginPageDelegate ------------------------------------------------------
 
 webkit::npapi::WebPluginDelegate* TestWebViewDelegate::CreatePluginDelegate(
-    const FilePath& path,
+    const base::FilePath& path,
     const std::string& mime_type) {
   HWND hwnd = shell_->webViewHost()->view_handle();
   if (!hwnd)
diff --git a/webkit/tools/webcore_unit_tests/ICOImageDecoder_unittest.cpp b/webkit/tools/webcore_unit_tests/ICOImageDecoder_unittest.cpp
index f4cdd3dedfbe1d..0c905ca16c4dff 100644
--- a/webkit/tools/webcore_unit_tests/ICOImageDecoder_unittest.cpp
+++ b/webkit/tools/webcore_unit_tests/ICOImageDecoder_unittest.cpp
@@ -26,8 +26,8 @@ TEST_F(ICOImageDecoderTest, Decoding) {
 TEST_F(ICOImageDecoderTest, ImageNonZeroFrameIndex) {
   // Test that the decoder decodes multiple sizes of icons which have them.
   // Load an icon that has both favicon-size and larger entries.
-  FilePath multisize_icon_path(data_dir_.AppendASCII("yahoo.ico"));
-  const FilePath md5_sum_path(
+  base::FilePath multisize_icon_path(data_dir_.AppendASCII("yahoo.ico"));
+  const base::FilePath md5_sum_path(
       GetMD5SumPath(multisize_icon_path).value() + FILE_PATH_LITERAL("2"));
   static const int kDesiredFrameIndex = 3;
   TestWebKitImageDecoder(multisize_icon_path, md5_sum_path, kDesiredFrameIndex);
diff --git a/win8/delegate_execute/chrome_util.cc b/win8/delegate_execute/chrome_util.cc
index 701f2e84dd82f7..b67e80f35c0431 100644
--- a/win8/delegate_execute/chrome_util.cc
+++ b/win8/delegate_execute/chrome_util.cc
@@ -36,7 +36,8 @@ const wchar_t kAppUserModelId[] = L"Chromium";
 
 // TODO(grt): These constants live in installer_util.  Consider moving them
 // into common_constants to allow for reuse.
-const FilePath::CharType kNewChromeExe[] = FILE_PATH_LITERAL("new_chrome.exe");
+const base::FilePath::CharType kNewChromeExe[] =
+    FILE_PATH_LITERAL("new_chrome.exe");
 const wchar_t kRenameCommandValue[] = L"cmd";
 const wchar_t kChromeAppGuid[] = L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
 const wchar_t kRegPathChromeClient[] =
@@ -48,7 +49,7 @@ const int kExitCodeRenameSuccessful = 23;
 // use by a browser process.
 // TODO(grt): Move this somewhere central so it can be used by both this
 // IsBrowserRunning (below) and IsBrowserAlreadyRunning (browser_util_win.cc).
-string16 GetEventName(const FilePath& chrome_exe) {
+string16 GetEventName(const base::FilePath& chrome_exe) {
   static wchar_t const kEventPrefix[] = L"Global\\";
   const size_t prefix_len = arraysize(kEventPrefix) - 1;
   string16 name;
@@ -63,7 +64,7 @@ string16 GetEventName(const FilePath& chrome_exe) {
 
 // Returns true if |chrome_exe| is in use by a browser process. In this case,
 // "in use" means past ChromeBrowserMainParts::PreMainMessageLoopRunImpl.
-bool IsBrowserRunning(const FilePath& chrome_exe) {
+bool IsBrowserRunning(const base::FilePath& chrome_exe) {
   base::win::ScopedHandle handle(::OpenEvent(
       SYNCHRONIZE, FALSE, GetEventName(chrome_exe).c_str()));
   if (handle.IsValid())
@@ -78,8 +79,8 @@ bool IsBrowserRunning(const FilePath& chrome_exe) {
 
 // Returns true if the file new_chrome.exe exists in the same directory as
 // |chrome_exe|.
-bool NewChromeExeExists(const FilePath& chrome_exe) {
-  FilePath new_chrome_exe(chrome_exe.DirName().Append(kNewChromeExe));
+bool NewChromeExeExists(const base::FilePath& chrome_exe) {
+  base::FilePath new_chrome_exe(chrome_exe.DirName().Append(kNewChromeExe));
   return file_util::PathExists(new_chrome_exe);
 }
 
@@ -93,7 +94,7 @@ bool GetUpdateCommand(bool is_per_user, string16* update_command) {
 #endif  // GOOGLE_CHROME_BUILD
 
 // TODO(grt): This code also lives in installer_util.  Refactor for reuse.
-bool IsPerUserInstall(const FilePath& chrome_exe) {
+bool IsPerUserInstall(const base::FilePath& chrome_exe) {
   wchar_t program_files_path[MAX_PATH] = {0};
   if (SUCCEEDED(SHGetFolderPath(NULL, CSIDL_PROGRAM_FILES, NULL,
                                 SHGFP_TYPE_CURRENT, program_files_path))) {
@@ -188,7 +189,7 @@ bool GetUserSpecificRegistrySuffix(string16* suffix) {
 
 namespace delegate_execute {
 
-void UpdateChromeIfNeeded(const FilePath& chrome_exe) {
+void UpdateChromeIfNeeded(const base::FilePath& chrome_exe) {
 #if defined(GOOGLE_CHROME_BUILD)
   // Nothing to do if a browser is already running or if there's no
   // new_chrome.exe.
@@ -253,7 +254,7 @@ void UpdateChromeIfNeeded(const FilePath& chrome_exe) {
 }
 
 // TODO(gab): This code also lives in shell_util. Refactor for reuse.
-string16 GetAppId(const FilePath& chrome_exe) {
+string16 GetAppId(const base::FilePath& chrome_exe) {
   string16 app_id(kAppUserModelId);
   string16 suffix;
   if (IsPerUserInstall(chrome_exe) &&
diff --git a/win8/delegate_execute/chrome_util.h b/win8/delegate_execute/chrome_util.h
index 634ce6c0fcbd0e..f65ec2fddf3bf8 100644
--- a/win8/delegate_execute/chrome_util.h
+++ b/win8/delegate_execute/chrome_util.h
@@ -7,15 +7,17 @@
 
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace delegate_execute {
 
 // Finalizes a previously updated installation.
-void UpdateChromeIfNeeded(const FilePath& chrome_exe);
+void UpdateChromeIfNeeded(const base::FilePath& chrome_exe);
 
 // Returns the appid of the Chrome pointed to by |chrome_exe|.
-string16 GetAppId(const FilePath& chrome_exe);
+string16 GetAppId(const base::FilePath& chrome_exe);
 
 }  // namespace delegate_execute
 
diff --git a/win8/delegate_execute/command_execute_impl.cc b/win8/delegate_execute/command_execute_impl.cc
index 96ca46b1023bf9..18ba4e7ead6f90 100644
--- a/win8/delegate_execute/command_execute_impl.cc
+++ b/win8/delegate_execute/command_execute_impl.cc
@@ -60,12 +60,12 @@ HRESULT GetUrlFromShellItem(IShellItem* shell_item, string16* url) {
 }
 
 bool LaunchChromeBrowserProcess() {
-  FilePath delegate_exe_path;
+  base::FilePath delegate_exe_path;
   if (!PathService::Get(base::FILE_EXE, &delegate_exe_path))
     return false;
 
   // First try and go up a level to find chrome.exe.
-  FilePath chrome_exe_path =
+  base::FilePath chrome_exe_path =
       delegate_exe_path.DirName()
                        .DirName()
                        .Append(chrome::kBrowserProcessExecutableName);
@@ -242,7 +242,7 @@ STDMETHODIMP CommandExecuteImpl::GetValue(enum AHE_TYPE* pahe) {
     return S_OK;
   }
 
-  FilePath user_data_dir;
+  base::FilePath user_data_dir;
   if (!PathService::Get(chrome::DIR_USER_DATA, &user_data_dir))  {
     AtlTrace("Failed to get chrome's data dir path, E_FAIL\n");
     return E_FAIL;
@@ -376,11 +376,11 @@ STDMETHODIMP CommandExecuteImpl::AllowForegroundTransfer(void* reserved) {
 
 // Returns false if chrome.exe cannot be found.
 // static
-bool CommandExecuteImpl::FindChromeExe(FilePath* chrome_exe) {
+bool CommandExecuteImpl::FindChromeExe(base::FilePath* chrome_exe) {
   AtlTrace("In %hs\n", __FUNCTION__);
   // Look for chrome.exe one folder above delegate_execute.exe (as expected in
   // Chrome installs). Failing that, look for it alonside delegate_execute.exe.
-  FilePath dir_exe;
+  base::FilePath dir_exe;
   if (!PathService::Get(base::DIR_EXE, &dir_exe)) {
     AtlTrace("Failed to get current exe path\n");
     return false;
diff --git a/win8/delegate_execute/command_execute_impl.h b/win8/delegate_execute/command_execute_impl.h
index 8e0fcbf61ec42c..1b137d9d051a7d 100644
--- a/win8/delegate_execute/command_execute_impl.h
+++ b/win8/delegate_execute/command_execute_impl.h
@@ -85,7 +85,7 @@ class ATL_NO_VTABLE DECLSPEC_UUID("A2DF06F9-A21A-44A8-8A99-8B9C84F29160")
   STDMETHOD(AllowForegroundTransfer)(void* reserved);
 
  private:
-  static bool FindChromeExe(FilePath* chrome_exe);
+  static bool FindChromeExe(base::FilePath* chrome_exe);
 
   static bool path_provider_initialized_;
 
@@ -96,7 +96,7 @@ class ATL_NO_VTABLE DECLSPEC_UUID("A2DF06F9-A21A-44A8-8A99-8B9C84F29160")
 
   CComPtr<IShellItemArray> item_array_;
   CommandLine parameters_;
-  FilePath chrome_exe_;
+  base::FilePath chrome_exe_;
   STARTUPINFO start_info_;
   string16 verb_;
   string16 display_name_;
diff --git a/win8/delegate_execute/delegate_execute_operation.cc b/win8/delegate_execute/delegate_execute_operation.cc
index f4aaa41bc9355f..9663828b6ab222 100644
--- a/win8/delegate_execute/delegate_execute_operation.cc
+++ b/win8/delegate_execute/delegate_execute_operation.cc
@@ -20,7 +20,8 @@ DelegateExecuteOperation::~DelegateExecuteOperation() {
 }
 
 bool DelegateExecuteOperation::Init(const CommandLine* cmd_line) {
-  FilePath shortcut(cmd_line->GetSwitchValuePath(switches::kRelaunchShortcut));
+  base::FilePath shortcut(
+      cmd_line->GetSwitchValuePath(switches::kRelaunchShortcut));
   if (shortcut.empty()) {
     operation_type_ = DELEGATE_EXECUTE;
     return true;
diff --git a/win8/delegate_execute/delegate_execute_operation.h b/win8/delegate_execute/delegate_execute_operation.h
index 3fc1b00a8b6fba..8d2900d27074dd 100644
--- a/win8/delegate_execute/delegate_execute_operation.h
+++ b/win8/delegate_execute/delegate_execute_operation.h
@@ -60,14 +60,14 @@ class DelegateExecuteOperation {
   // Returns the process id of the parent or 0 on failure.
   DWORD GetParentPid() const;
 
-  const FilePath& shortcut() const {
+  const base::FilePath& shortcut() const {
     return relaunch_shortcut_;
   }
 
  private:
   OperationType operation_type_;
   string16 relaunch_flags_;
-  FilePath relaunch_shortcut_;
+  base::FilePath relaunch_shortcut_;
   string16 mutex_;
 
   DISALLOW_COPY_AND_ASSIGN(DelegateExecuteOperation);
diff --git a/win8/delegate_execute/delegate_execute_util.cc b/win8/delegate_execute/delegate_execute_util.cc
index d04c667b9c233e..70ca3e38b423d7 100644
--- a/win8/delegate_execute/delegate_execute_util.cc
+++ b/win8/delegate_execute/delegate_execute_util.cc
@@ -16,13 +16,13 @@ CommandLine CommandLineFromParameters(const wchar_t* params) {
     string16 command_string(L"noprogram.exe ");
     command_string.append(params);
     command_line.ParseFromString(command_string);
-    command_line.SetProgram(FilePath());
+    command_line.SetProgram(base::FilePath());
   }
 
   return command_line;
 }
 
-CommandLine MakeChromeCommandLine(const FilePath& chrome_exe,
+CommandLine MakeChromeCommandLine(const base::FilePath& chrome_exe,
                                   const CommandLine& params,
                                   const string16& argument) {
   CommandLine chrome_cmd(params);
diff --git a/win8/delegate_execute/delegate_execute_util.h b/win8/delegate_execute/delegate_execute_util.h
index 5f001ff7bc3314..36f15564600dd7 100644
--- a/win8/delegate_execute/delegate_execute_util.h
+++ b/win8/delegate_execute/delegate_execute_util.h
@@ -8,7 +8,9 @@
 #include "base/command_line.h"
 #include "base/string16.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace delegate_execute {
 
@@ -17,7 +19,7 @@ CommandLine CommandLineFromParameters(const wchar_t* params);
 
 // Returns a CommandLine to launch |chrome_exe| with all switches and arguments
 // from |params| plus an optional |argument|.
-CommandLine MakeChromeCommandLine(const FilePath& chrome_exe,
+CommandLine MakeChromeCommandLine(const base::FilePath& chrome_exe,
                                   const CommandLine& params,
                                   const string16& argument);
 
diff --git a/win8/delegate_execute/delegate_execute_util_unittest.cc b/win8/delegate_execute/delegate_execute_util_unittest.cc
index 360d8e7785ccd7..6fcf65df9cc781 100644
--- a/win8/delegate_execute/delegate_execute_util_unittest.cc
+++ b/win8/delegate_execute/delegate_execute_util_unittest.cc
@@ -36,7 +36,7 @@ TEST(DelegateExecuteUtil, CommandLineFromParametersTest) {
 TEST(DelegateExecuteUtil, MakeChromeCommandLineTest) {
   static const wchar_t kSomeArgument[] = L"http://some.url/";
   static const wchar_t kOtherArgument[] = L"http://some.other.url/";
-  const FilePath this_exe(CommandLine::ForCurrentProcess()->GetProgram());
+  const base::FilePath this_exe(CommandLine::ForCurrentProcess()->GetProgram());
 
   CommandLine cl(CommandLine::NO_PROGRAM);
 
diff --git a/win8/metro_driver/file_picker_ash.h b/win8/metro_driver/file_picker_ash.h
index ec8cf6ae12e997..4426f5cc7431a8 100644
--- a/win8/metro_driver/file_picker_ash.h
+++ b/win8/metro_driver/file_picker_ash.h
@@ -10,10 +10,13 @@
 #include "base/compiler_specific.h"
 #include "base/string16.h"
 
-class FilePath;
 class ChromeAppViewAsh;
 struct MetroViewerHostMsg_SaveAsDialogParams;
 
+namespace base {
+class FilePath;
+}
+
 // Base class for the file pickers.
 class FilePickerSessionBase {
  public:
@@ -79,7 +82,7 @@ class OpenFilePickerSession : public FilePickerSessionBase {
                                  const string16& default_path,
                                  bool allow_multi_select);
 
-  const std::vector<FilePath>& filenames() const {
+  const std::vector<base::FilePath>& filenames() const {
     return filenames_;
   }
 
@@ -113,7 +116,7 @@ class OpenFilePickerSession : public FilePickerSessionBase {
   bool allow_multi_select_;
   // If multi select is true then this member contains the list of filenames
   // to be returned back.
-  std::vector<FilePath> filenames_;
+  std::vector<base::FilePath> filenames_;
 
   DISALLOW_COPY_AND_ASSIGN(OpenFilePickerSession);
 };