Remove GetAudioManager and GetMediaStreamManager from ResourceContext. The reason is the content mo…

media/audio/audio_manager.cc

 // Copyright (c) 2012 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 "media/audio/audio_manager.h"
 
 #include "base/at_exit.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 
-// Used only to make sure we never create more than one instance.
-static AudioManager* g_audio_manager = NULL;
-
 // Forward declaration of the platform specific AudioManager factory function.
 AudioManager* CreateAudioManager();
 
 AudioManager::AudioManager() {
-  CHECK(g_audio_manager == NULL);
-  g_audio_manager = this;
 }
 
 AudioManager::~AudioManager() {
-  CHECK(g_audio_manager == this);
-  g_audio_manager = NULL;
 }
 
 // static
 AudioManager* AudioManager::Create() {
   AudioManager* ret = CreateAudioManager();
-  DCHECK(ret == g_audio_manager);
   ret->Init();
   return ret;
 }