Always delete media galleries FilePathWatchers on the FILE thread.

chrome/browser/media_galleries/fileapi/picasa_data_provider.cc

 // Copyright 2013 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 "chrome/browser/media_galleries/fileapi/picasa_data_provider.h"
 
 #include <utility>
 
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/files/file_util.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/stringprintf.h"
-#include "chrome/browser/media_galleries/fileapi/file_path_watcher_util.h"
 #include "chrome/browser/media_galleries/fileapi/media_file_system_backend.h"
 #include "chrome/browser/media_galleries/fileapi/safe_picasa_album_table_reader.h"
 #include "chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h"
 #include "chrome/browser/media_galleries/imported_media_gallery_registry.h"
 #include "storage/browser/fileapi/file_system_operation_context.h"
 #include "storage/browser/fileapi/file_system_url.h"
 
 namespace picasa {
 
 namespace {
@@ skipping 19 matching lines @@
   MediaFileSystemBackend::AssertCurrentlyOnMediaSequence();
 
   StartFilePathWatchOnMediaTaskRunner(
       database_path_.DirName().AppendASCII(kPicasaTempDirName),
       base::Bind(&PicasaDataProvider::OnTempDirWatchStarted,
                  weak_factory_.GetWeakPtr()),
       base::Bind(&PicasaDataProvider::OnTempDirChanged,
                  weak_factory_.GetWeakPtr()));
 }
 
-PicasaDataProvider::~PicasaDataProvider() {
-  StopFilePathWatchOnMediaTaskRunner(std::move(temp_dir_watcher_));
-}
+PicasaDataProvider::~PicasaDataProvider() {}
 
 void PicasaDataProvider::RefreshData(DataType needed_data,
                                      const ReadyCallback& ready_callback) {
   MediaFileSystemBackend::AssertCurrentlyOnMediaSequence();
   // TODO(tommycli): Need to watch the database_path_ folder and handle
   // rereading the data when it changes.
 
   if (state_ == INVALID_DATA_STATE) {
     ready_callback.Run(false /* success */);
     return;
@@ skipping 55 matching lines @@
   // TODO(tommycli): Implement and call Cancel function for these
   // UtilityProcessHostClients to actually kill the in-flight processes.
   state_ = STALE_DATA_STATE;
   album_table_reader_ = NULL;
   albums_indexer_ = NULL;
 
   DoRefreshIfNecessary();
 }
 
 void PicasaDataProvider::OnTempDirWatchStarted(
-    std::unique_ptr<base::FilePathWatcher> temp_dir_watcher) {
+    MediaFilePathWatcherUniquePtr temp_dir_watcher) {
   MediaFileSystemBackend::AssertCurrentlyOnMediaSequence();
   temp_dir_watcher_ = std::move(temp_dir_watcher);
 }
 
 void PicasaDataProvider::OnTempDirChanged(const base::FilePath& temp_dir_path,
                                           bool error) {
   MediaFileSystemBackend::AssertCurrentlyOnMediaSequence();
   if (base::IsDirectoryEmpty(temp_dir_path))
     InvalidateData();
 }
@@ skipping 117 matching lines @@
     if (total_counts[name] != 1) {
       name = base::StringPrintf("%s (%d)", name.c_str(),
                                 ++current_counts[name]);
     }
 
     result_map->insert(std::pair<std::string, AlbumInfo>(name, info_list[i]));
   }
 }
 
 }  // namespace picasa