Pass FROM_HERE to ObserverListThreadSafe::Notify to improve profile.

chrome/browser/sync_file_system/local/canned_syncable_file_system.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/sync_file_system/local/canned_syncable_file_system.h"
 
 #include <algorithm>
 #include <iterator>
 
 #include "base/bind.h"
@@ skipping 532 matching lines @@
 
 SyncFileSystemBackend* CannedSyncableFileSystem::backend() {
   return SyncFileSystemBackend::GetBackend(file_system_context_.get());
 }
 
 FileSystemOperationRunner* CannedSyncableFileSystem::operation_runner() {
   return file_system_context_->operation_runner();
 }
 
 void CannedSyncableFileSystem::OnSyncEnabled(const FileSystemURL& url) {
-  sync_status_observers_->Notify(&LocalFileSyncStatus::Observer::OnSyncEnabled,
-                                 url);
+  sync_status_observers_->Notify(
+      FROM_HERE, &LocalFileSyncStatus::Observer::OnSyncEnabled, url);
 }
 
 void CannedSyncableFileSystem::OnWriteEnabled(const FileSystemURL& url) {
-  sync_status_observers_->Notify(&LocalFileSyncStatus::Observer::OnWriteEnabled,
-                                 url);
+  sync_status_observers_->Notify(
+      FROM_HERE, &LocalFileSyncStatus::Observer::OnWriteEnabled, url);
 }
 
 void CannedSyncableFileSystem::DoOpenFileSystem(
     const OpenFileSystemCallback& callback) {
   EXPECT_TRUE(io_task_runner_->RunsTasksOnCurrentThread());
   EXPECT_FALSE(is_filesystem_opened_);
   file_system_context_->OpenFileSystem(
       origin_,
       type_,
       storage::OPEN_FILE_SYSTEM_CREATE_IF_NONEXISTENT,
@@ skipping 187 matching lines @@
   sync_status_ = status;
   quit_closure.Run();
 }
 
 void CannedSyncableFileSystem::InitializeSyncStatusObserver() {
   ASSERT_TRUE(io_task_runner_->RunsTasksOnCurrentThread());
   backend()->sync_context()->sync_status()->AddObserver(this);
 }
 
 }  // namespace sync_file_system