Implementation of 'AudioContext.getOutputTimestamp' method

media/base/audio_renderer_sink.h

Index: media/base/audio_renderer_sink.h
diff --git a/media/base/audio_renderer_sink.h b/media/base/audio_renderer_sink.h
index 268b9b6c45c33f2bfb02fc4352fb010bd7aed28e..be0a1e303538b8ccf8b2c5be1d11c21818675a78 100644
--- a/media/base/audio_renderer_sink.h
+++ b/media/base/audio_renderer_sink.h
@@ -18,6 +18,8 @@
 
 namespace media {
 
+struct AudioTimestamp;
+
 // AudioRendererSink is an interface representing the end-point for
 // rendered audio.  An implementation is expected to
 // periodically call Render() on a callback object.
@@ -25,14 +27,20 @@ namespace media {
 class AudioRendererSink
     : public base::RefCountedThreadSafe<media::AudioRendererSink> {
  public:
-  class RenderCallback {
+  class MEDIA_EXPORT RenderCallback {
    public:
     // Attempts to completely fill all channels of |dest|, returns actual
     // number of frames filled. |frames_skipped| contains the number of frames
     // the consumer has skipped, if any.
     virtual int Render(AudioBus* dest,
                        uint32_t frames_delayed,
-                       uint32_t frames_skipped) = 0;
+                       uint32_t frames_skipped);
+    // An alternate version which provides also device stream position,
+    // if not overriden it just invokes the method above.
+    virtual int Render(AudioBus* dest,
+                       uint32_t audio_delay_milliseconds,
+                       uint32_t frames_skipped,
+                       const AudioTimestamp& output_timestamp);
 
     // Signals an error has occurred.
     virtual void OnRenderError() = 0;