First step towards moving AudioDevice from content/ to media/audio.

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 AudioRendererSink;
 }
 
+class AudioInputDevice;
+
 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.
 // This class uses the same pattern as content::RenderViewHostFactory.
 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* Create();
+ static media::AudioRendererSink* NewOutputDevice();
+
+ // TODO(henrika): Update AudioInputDevice to inherit from an interface
+ // similar to AudioRendererSink, but for input.  Same for the callback
+ // interfaces.
+ static AudioInputDevice* NewInputDevice();
 
  protected:
   AudioDeviceFactory();
   virtual ~AudioDeviceFactory();
 
-  // You can derive from this class and specify an implementation for this
-  // function to create a different kind of AudioRendererSink for testing.
-  virtual media::AudioRendererSink* CreateAudioDevice() = 0;
+  // 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 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_