Plumb render view ID from audio-related code in renderer through IPCs to AudioRendererHost in brows…

content/renderer/media/audio_device_factory.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 CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_FACTORY_H_
 #define CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_FACTORY_H_
 
 #include "base/basictypes.h"
 #include "content/common/content_export.h"
 
 namespace media {
 class AudioInputDevice;
 class AudioRendererSink;
 }
 
 namespace content {
 
 // A factory for creating AudioRendererSinks. There is a global factory
 // function that can be installed for the purposes of testing to provide
 // a specialized AudioRendererSink class.
 class CONTENT_EXPORT AudioDeviceFactory {
  public:
   // Creates an AudioRendererSink using the currently registered factory,
   // or the default one if no factory is registered. Ownership of the returned
-  // pointer will be passed to the caller.
-  static media::AudioRendererSink* NewOutputDevice();
+  // pointer will be passed to the caller.  |render_view_id| refers to the
+  // source of the output.
+  static media::AudioRendererSink* NewOutputDevice(
+      int render_view_id);
 
   // TODO(henrika): Update AudioInputDevice to inherit from an interface
   // similar to AudioRendererSink, but for input.  Same for the callback
   // interfaces.
   static media::AudioInputDevice* NewInputDevice();
 
  protected:
   AudioDeviceFactory();
   virtual ~AudioDeviceFactory();
 
   // You can derive from this class and specify an implementation for these
   // functions to provide alternate audio device implementations.
   // If the return value of either of these function is NULL, we fall back
   // on the default implementation.
-  virtual media::AudioRendererSink* CreateOutputDevice() = 0;
+  virtual media::AudioRendererSink* CreateOutputDevice(int render_view_id) = 0;
   virtual media::AudioInputDevice* CreateInputDevice() = 0;
 
  private:
   // The current globally registered factory. This is NULL when we should
   // create the default AudioRendererSinks.
   static AudioDeviceFactory* factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioDeviceFactory);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_FACTORY_H_