dbus: Reuse is_set() function from ScopedDBusError API.

R=satorux@chromium.org
TEST=dbus_unittests

Review URL: https://codereview.chromium.org/11266020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@164651 0039d316-1c4b-4281-b951-d872f2087c98

dbus/bus.cc

@@ -305,7 +305,7 @@ bool Bus::Connect() {
   }
   if (!connection_) {
     LOG(ERROR) << "Failed to connect to the bus: "
-               << (dbus_error_is_set(error.get()) ? error.message() : "");
+               << (error.is_set() ? error.message() : "");
     return false;
   }
   // We shouldn't exit on the disconnected signal.
@@ -429,7 +429,7 @@ bool Bus::RequestOwnershipAndBlock(const std::string& service_name) {
                                            error.get());
   if (result != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER) {
     LOG(ERROR) << "Failed to get the ownership of " << service_name << ": "
-               << (dbus_error_is_set(error.get()) ? error.message() : "");
+               << (error.is_set() ? error.message() : "");
     return false;
   }
   owned_service_names_.insert(service_name);

dbus/scoped_dbus_error.h

@@ -21,7 +21,7 @@ class ScopedDBusError {
   }
 
   DBusError* get() { return &error_; }
-  bool is_set() { return dbus_error_is_set(&error_); }
+  bool is_set() const { return dbus_error_is_set(&error_); }
   const char* name() { return error_.name; }
   const char* message() { return error_.message; }