Share one thread between all AudioOutputControllers instead of creating one per stream.

media/audio/audio_input_controller.h

 // Copyright (c) 2010 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_INPUT_CONTROLLER_H_
 #define MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_
 
 #include "base/lock.h"
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 #include "base/thread.h"
 #include "media/audio/audio_io.h"
+#include "media/audio/audio_manager.h"
 
 // An AudioInputController controls an AudioInputStream and records data
 // from this input stream. It has an important function that it executes
 // audio operations like record, pause, stop, etc. on a separate thread.
 //
 // All the public methods of AudioInputController are non-blocking except
 // close, the actual operations are performed on the audio input controller
 // thread.
 //
 // Here is a state diagram for the AudioInputController:
@@ skipping 113 matching lines @@
   base::Thread thread_;
 
   static Factory* factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioInputController);
 };
 
 }  // namespace media
 
 #endif  //  MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_