Introduce AudioHardwareConfig for renderer side audio device info.

content/renderer/media/audio_message_filter.h

Index: content/renderer/media/audio_message_filter.h
diff --git a/content/renderer/media/audio_message_filter.h b/content/renderer/media/audio_message_filter.h
index de746d5d31cd7767ee20ff4cdcf787dbf9603fbf..93dafd2f6a5c470512f4752bf9cac1865fc4a32f 100644
--- a/content/renderer/media/audio_message_filter.h
+++ b/content/renderer/media/audio_message_filter.h
@@ -75,6 +75,10 @@ class CONTENT_EXPORT AudioMessageFilter
   void OnStreamStateChanged(int stream_id,
                             media::AudioOutputIPCDelegate::State state);
 
+  // Received when the browser process detects an output device change.
+  void OnOutputDeviceChanged(int stream_id, int new_buffer_size,
+                             int new_sample_rate);
+
   // The singleton instance for this filter.
   static AudioMessageFilter* filter_;