[SyncFS] Make ExtensionService usage of SyncWorker asynchronous

chrome/browser/sync_file_system/drive_backend/callback_helper.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/sync_file_system/drive_backend/callback_helper.h"
+
+namespace sync_file_system {
+namespace drive_backend {
+
+namespace internal {

[peria, 2014/04/24 02:38:21]

anonymous namespace?

[tzik, 2014/04/24 06:56:55]

Refactored.

+
+void RelayToTaskRunner0(base::SequencedTaskRunner* task_runner,
+                        const tracked_objects::Location& from_here,
+                        const base::Callback<void()>& callback) {
+  task_runner->PostTask(
+      from_here, base::Bind(callback));
+}
+
+}
+
+base::Callback<void()> CreateRelayedCallback(
+    const base::Callback<void()>& callback) {
+  return base::Bind(&internal::RelayToTaskRunner0,
+                    base::MessageLoopProxy::current(),
+                    FROM_HERE,
+                    callback);
+}
+
+}  // namespace drive_backend
+}  // namespace sync_file_system