Reland 15721002: Hook up the device selection to the WebAudio live audio

media/audio/audio_output_ipc.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_OUTPUT_IPC_H_
 #define MEDIA_AUDIO_AUDIO_OUTPUT_IPC_H_
 
 #include "base/shared_memory.h"
 #include "base/sync_socket.h"
 #include "media/audio/audio_parameters.h"
@@ skipping 43 matching lines @@
 // Provides the IPC functionality for an AudioOutputIPCDelegate (e.g., an
 // AudioOutputDevice).  The implementation should asynchronously deliver the
 // messages to an AudioOutputController object (or create one in the case of
 // CreateStream()), that may live in a separate process.
 class MEDIA_EXPORT AudioOutputIPC {
  public:
   virtual ~AudioOutputIPC();
 
   // Sends a request to create an AudioOutputController object in the peer
   // process and configures it to use the specified audio |params| including
-  // number of synchronized input channels.  Once the stream has been created,
+  // number of synchronized input channels.|session_id| is used by the browser
+  // to select the correct input device if the input channel in |params| is
+  // valid, otherwise it will be ignored.  Once the stream has been created,
   // the implementation will notify |delegate| by calling OnStreamCreated().
   virtual void CreateStream(AudioOutputIPCDelegate* delegate,
-                            const AudioParameters& params) = 0;
+                            const AudioParameters& params,
+                            int session_id) = 0;
 
   // Starts playing the stream.  This should generate a call to
   // AudioOutputController::Play().
   virtual void PlayStream() = 0;
 
   // Pauses an audio stream.  This should generate a call to
   // AudioOutputController::Pause().
   virtual void PauseStream() = 0;
 
   // Closes the audio stream which should shut down the corresponding
   // AudioOutputController in the peer process.
   virtual void CloseStream() = 0;
 
   // Sets the volume of the audio stream.
   virtual void SetVolume(double volume) = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_OUTPUT_IPC_H_