[fsp] Add support for observing entries and notifying about changes.

chrome/browser/chromeos/file_system_provider/fake_provided_file_system.cc

 // Copyright 2014 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/chromeos/file_system_provider/fake_provided_file_system.h"
 
 #include "base/files/file.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "net/base/io_buffer.h"
 
@@ skipping 313 matching lines @@
 const ProvidedFileSystemInfo& FakeProvidedFileSystem::GetFileSystemInfo()
     const {
   return file_system_info_;
 }
 
 RequestManager* FakeProvidedFileSystem::GetRequestManager() {
   NOTREACHED();
   return NULL;
 }
 
+void FakeProvidedFileSystem::AddObserver(Observer* observer) {
+  DCHECK(observer);
+  observers_.AddObserver(observer);
+}
+
+void FakeProvidedFileSystem::RemoveObserver(Observer* observer) {
+  DCHECK(observer);
+  observers_.RemoveObserver(observer);
+}
+
+ObserverList<ProvidedFileSystemInterface::Observer>*
+FakeProvidedFileSystem::GetObservers() {
+  return &observers_;
+}
+
 ProvidedFileSystemInterface* FakeProvidedFileSystem::Create(
     Profile* profile,
     const ProvidedFileSystemInfo& file_system_info) {
   return new FakeProvidedFileSystem(file_system_info);
 }
 
 base::WeakPtr<ProvidedFileSystemInterface>
 FakeProvidedFileSystem::GetWeakPtr() {
   return weak_ptr_factory_.GetWeakPtr();
 }
@@ skipping 17 matching lines @@
     const std::vector<int>& task_ids,
     const storage::AsyncFileUtil::StatusCallback& callback) {
   for (size_t i = 0; i < task_ids.size(); ++i) {
     tracker_.TryCancel(task_ids[i]);
   }
   callback.Run(base::File::FILE_OK);
 }
 
 }  // namespace file_system_provider
 }  // namespace chromeos