Remove the AudioManager singleton.

media/audio/mac/audio_manager_mac.cc

 // Copyright (c) 2011 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 <CoreAudio/AudioHardware.h>
 
 #include "base/mac/mac_util.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/sys_string_conversions.h"
 #include "media/audio/fake_audio_input_stream.h"
@@ skipping 315 matching lines @@
   DCHECK(stream);
   num_output_streams_--;
   delete stream;
 }
 
 // Called by the stream when it has been released by calling Close().
 void AudioManagerMac::ReleaseInputStream(AudioInputStream* stream) {
   delete stream;
 }
 
-// static
-AudioManager* AudioManager::CreateAudioManager() {
+AudioManager* CreateAudioManager() {
   return new AudioManagerMac();
 }