Introduce AudioHardwareConfig for renderer side audio device info.

content/common/media/audio_messages.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.
 
 // IPC messages for the audio.
 // Multiply-included message file, hence no include guard.
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 45 matching lines @@
                      base::SyncSocket::Handle /* socket handle */,
                      uint32 /* length */)
 #else
 IPC_MESSAGE_CONTROL4(AudioInputMsg_NotifyStreamCreated,
                      int /* stream id */,
                      base::SharedMemoryHandle /* handle */,
                      base::FileDescriptor /* socket handle */,
                      uint32 /* length */)
 #endif
 
+// Notification message sent from AudioRendererHost to renderer after an output
+// device change has occurred.
+IPC_MESSAGE_CONTROL3(AudioMsg_NotifyDeviceChanged,
+                     int /* stream_id */,
+                     int /* new_buffer_size */,
+                     int /* new_sample_rate */)
+
 // Notification message sent from AudioRendererHost to renderer for state
 // update after the renderer has requested a Create/Start/Close.
 IPC_MESSAGE_CONTROL2(AudioMsg_NotifyStreamStateChanged,
                      int /* stream id */,
                      media::AudioOutputIPCDelegate::State /* new state */)
 
 // Notification message sent from browser to renderer for state update.
 IPC_MESSAGE_CONTROL2(AudioInputMsg_NotifyStreamStateChanged,
                      int /* stream id */,
                      media::AudioInputIPCDelegate::State /* new state */)
@@ skipping 64 matching lines @@
 // Set audio volume of the input stream specified by stream_id.
 IPC_MESSAGE_CONTROL2(AudioInputHostMsg_SetVolume,
                      int /* stream_id */,
                      double /* volume */)
 
 // Start the device referenced by the session_id for the input stream specified
 // by stream_id.
 IPC_MESSAGE_CONTROL2(AudioInputHostMsg_StartDevice,
                      int /* stream_id */,
                      int /* session_id */)