Move FilePathWatcher to base/files.

base/files/file_path_watcher.cc

 // Copyright (c) 2011 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.
 
 // Cross platform methods for FilePathWatcher. See the various platform
 // specific implementation files, too.
 
-#include "content/common/file_path_watcher/file_path_watcher.h"
+#include "base/files/file_path_watcher.h"
 
 #include "base/logging.h"
 #include "base/message_loop.h"
 
+namespace base {
+namespace files {
+
 FilePathWatcher::~FilePathWatcher() {
   impl_->Cancel();
 }
 
 bool FilePathWatcher::Watch(const FilePath& path, Delegate* delegate) {
   DCHECK(path.IsAbsolute());
   return impl_->Watch(path, delegate);
 }
 
 FilePathWatcher::PlatformDelegate::PlatformDelegate(): cancelled_(false) {
 }
 
 FilePathWatcher::PlatformDelegate::~PlatformDelegate() {
   DCHECK(is_cancelled());
 }
 
+}  // namespace files
+}  // namespace base