[fsp] Pass more detailed errors to the providing extension.

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 349 matching lines @@
   DCHECK(observer);
   observers_.AddObserver(observer);
 }
 
 void FakeProvidedFileSystem::RemoveObserver(
     ProvidedFileSystemObserver* observer) {
   DCHECK(observer);
   observers_.RemoveObserver(observer);
 }
 
-bool FakeProvidedFileSystem::Notify(
+void FakeProvidedFileSystem::Notify(
     const base::FilePath& entry_path,
     bool recursive,
     storage::WatcherManager::ChangeType change_type,
     scoped_ptr<ProvidedFileSystemObserver::Changes> changes,
-    const std::string& tag) {
+    const std::string& tag,
+    const storage::AsyncFileUtil::StatusCallback& callback) {
   NOTREACHED();
-  return false;
+  callback.Run(base::File::FILE_ERROR_SECURITY);
 }
 
 ProvidedFileSystemInterface* FakeProvidedFileSystem::Create(
     Profile* profile,
     const ProvidedFileSystemInfo& file_system_info) {
   return new FakeProvidedFileSystem(file_system_info);
 }
 
 base::WeakPtr<ProvidedFileSystemInterface>
 FakeProvidedFileSystem::GetWeakPtr() {
@@ skipping 19 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