Remove MmapSyncInterface.

Since Pepper is no longer supported, this interface can be removed.

PiperOrigin-RevId: 406036931

src/base/BUILD.bazel

@@ -644,19 +644,12 @@ cc_test_mozc(
     ],
 )
 
-cc_library_mozc(
-    name = "mmap_sync_interface",
-    hdrs = ["mmap_sync_interface.h"],
-    visibility = ["//visibility:private"],
-)
-
 cc_library_mozc(
     name = "mmap",
     srcs = ["mmap.cc"],
     hdrs = ["mmap.h"],
     deps = [
         ":logging",
-        ":mmap_sync_interface",
         ":port",
         ":scoped_handle",
         ":util",

src/base/mmap.h

@@ -30,18 +30,18 @@
 #ifndef MOZC_BASE_MMAP_H_
 #define MOZC_BASE_MMAP_H_
 
-#include <string>
-
-#include "base/mmap_sync_interface.h"
-#include "base/port.h"
-
+#include <cstddef>
 
 namespace mozc {
 
-class Mmap : public MmapSyncInterface {
+class Mmap final {
  public:
   Mmap();
-  ~Mmap() override { Close(); }
+
+  Mmap(const Mmap &) = delete;
+  Mmap &operator=(const Mmap &) = delete;
+
+  ~Mmap() { Close(); }
 
   bool Open(const char *filename, const char *mode = "r");
   void Close();
@@ -73,8 +73,6 @@ class Mmap : public MmapSyncInterface {
  private:
   char *text_;
   size_t size_;
-
-  DISALLOW_COPY_AND_ASSIGN(Mmap);
 };
 
 }  // namespace mozc