Use the browser UI thread for audio on OSX.

media/audio/audio_manager_base.h

 // 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.
 
 #ifndef MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_
 #define MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_
 
 #include <string>
 #include <utility>
 
@@ skipping 23 matching lines @@
 class MEDIA_EXPORT AudioManagerBase : public AudioManager {
  public:
   // Name of the generic "default" device.
   static const char kDefaultDeviceName[];
   // Unique Id of the generic "default" device.
   static const char kDefaultDeviceId[];
 
   virtual ~AudioManagerBase();
 
   virtual scoped_refptr<base::MessageLoopProxy> GetMessageLoop() OVERRIDE;
+  virtual scoped_refptr<base::MessageLoopProxy> GetWorkerLoop() OVERRIDE;
 
   virtual string16 GetAudioInputDeviceModel() OVERRIDE;
 
   virtual void ShowAudioInputSettings() OVERRIDE;
 
   virtual void GetAudioInputDeviceNames(
       media::AudioDeviceNames* device_names) OVERRIDE;
 
   virtual AudioOutputStream* MakeAudioOutputStream(
       const AudioParameters& params,
@@ skipping 114 matching lines @@
   // Map of cached AudioOutputDispatcher instances.  Must only be touched
   // from the audio thread (no locking).
   AudioOutputDispatchers output_dispatchers_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioManagerBase);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_