Pass delay and timestamp to AudioSourceCallback::OnMoreData.

media/base/audio_timestamp_helper.h

Index: media/base/audio_timestamp_helper.h
diff --git a/media/base/audio_timestamp_helper.h b/media/base/audio_timestamp_helper.h
index 40ac93cd3ef48e4e4e495719ef6195b66f01aa6c..1b599421e425601842dcbe4a4d33fdbcf6d0db31 100644
--- a/media/base/audio_timestamp_helper.h
+++ b/media/base/audio_timestamp_helper.h
@@ -30,6 +30,14 @@ namespace media {
 // accumulated frames to reach a target timestamp.
 class MEDIA_EXPORT AudioTimestampHelper {
  public:
+  // Returns the time duration of the given number of frames of audio with the
+  // given sample rate (in samples per second).
+  static base::TimeDelta FramesToTime(int64_t frames, int samples_per_second);
+
+  // Returns the number of frames in the given duration of audio with the given
+  // sample rate (in samples per second).
+  static int64_t TimeToFrames(base::TimeDelta time, int samples_per_second);
+
   explicit AudioTimestampHelper(int samples_per_second);
 
   // Sets the base timestamp to |base_timestamp| and the sets count to 0.