base: Add missing "virtual" keyword and OVERRIDE to some methods.

base/files/file_path_watcher_linux.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/files/file_path_watcher.h"
 
 #include <errno.h>
 #include <string.h>
 #include <sys/inotify.h>
 #include <sys/ioctl.h>
@@ skipping 97 matching lines @@
   // Deletion of the FilePathWatcher will call Cancel() to dispose of this
   // object in the right thread. This also observes destruction of the required
   // cleanup thread, in case it quits before Cancel() is called.
   virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
 
  protected:
   virtual ~FilePathWatcherImpl() {}
 
  private:
   // Cleans up and stops observing the |message_loop_| thread.
-  void CancelOnMessageLoopThread() OVERRIDE;
+  virtual void CancelOnMessageLoopThread() OVERRIDE;
 
   // Inotify watches are installed for all directory components of |target_|. A
   // WatchEntry instance holds the watch descriptor for a component and the
   // subdirectory for that identifies the next component. If a symbolic link
   // is being watched, the target of the link is also kept.
   struct WatchEntry {
     WatchEntry(InotifyReader::Watch watch, const FilePath::StringType& subdir)
         : watch_(watch),
           subdir_(subdir) {}
 
@@ skipping 345 matching lines @@
 }
 
 }  // namespace
 
 FilePathWatcher::FilePathWatcher() {
   impl_ = new FilePathWatcherImpl();
 }
 
 }  // namespace files
 }  // namespace base