Move Singleton and related structs to namespace base

chromecast/media/base/media_message_loop.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 "chromecast/media/base/media_message_loop.h"
 
 #include "base/threading/thread.h"
 
 namespace chromecast {
 namespace media {
 
 // static
 scoped_refptr<base::SingleThreadTaskRunner> MediaMessageLoop::GetTaskRunner() {
   return GetInstance()->thread_->task_runner();
 }
 
 // static
 MediaMessageLoop* MediaMessageLoop::GetInstance() {
-  return Singleton<MediaMessageLoop>::get();
+  return base::Singleton<MediaMessageLoop>::get();
 }
 
 MediaMessageLoop::MediaMessageLoop()
   : thread_(new base::Thread("CmaThread")) {
   thread_->Start();
 }
 
 MediaMessageLoop::~MediaMessageLoop() {
   // This will automatically shutdown the thread.
 }
 
 }  // namespace media
 }  // namespace chromecast