Add support for switching the audio output device for HTMLMediaElements.

media/audio/audio_output_stream_sink.h

Index: media/audio/audio_output_stream_sink.h
diff --git a/media/audio/audio_output_stream_sink.h b/media/audio/audio_output_stream_sink.h
index c6f04a7dafd4ca4829eeadc5d0495088ab732763..a2fe87bfccd66e9880c190dc975fc752e6e2cc80 100644
--- a/media/audio/audio_output_stream_sink.h
+++ b/media/audio/audio_output_stream_sink.h
@@ -5,12 +5,16 @@
 #ifndef MEDIA_AUDIO_AUDIO_OUTPUT_STREAM_SINK_H_
 #define MEDIA_AUDIO_AUDIO_OUTPUT_STREAM_SINK_H_
 
+#include <string>
+
+#include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "media/audio/audio_io.h"
 #include "media/base/audio_renderer_sink.h"
 #include "media/base/media_export.h"
+#include "url/gurl.h"
 
 namespace media {
 
@@ -34,6 +38,9 @@ class MEDIA_EXPORT AudioOutputStreamSink
   void Pause() override;
   void Play() override;
   bool SetVolume(double volume) override;
+  void SwitchOutputDevice(const std::string& device_id,
+                          const GURL& security_origin,
+                          const base::Callback<void(int)>& callback) override;
 
   // AudioSourceCallback implementation.
   int OnMoreData(AudioBus* dest, uint32 total_bytes_delay) override;