Introduce media::TimeSource.

media/base/pipeline.h

Index: media/base/pipeline.h
diff --git a/media/base/pipeline.h b/media/base/pipeline.h
index 6a408da23f0d18abaa66411044e58d37d6e29ecb..40a94978a7ae763ae875012f9703a73c27ff2f7d 100644
--- a/media/base/pipeline.h
+++ b/media/base/pipeline.h
@@ -33,8 +33,9 @@ class FilterCollection;
 class MediaLog;
 class TextRenderer;
 class TextTrackConfig;
-class TimeDeltaInterpolator;
+class TimeSource;
 class VideoRenderer;
+class WallClockTimeSource;
 
 // Metadata describing a pipeline once it has been initialized.
 struct PipelineMetadata {
@@ -179,7 +180,6 @@ class MEDIA_EXPORT Pipeline : public DemuxerHost {
   void set_underflow_disabled_for_testing(bool disabled) {
     underflow_disabled_for_testing_ = disabled;
   }
-  void SetTimeDeltaInterpolatorForTesting(TimeDeltaInterpolator* interpolator);
   void SetErrorForTesting(PipelineStatus status);
 
  private:
@@ -232,12 +232,6 @@ class MEDIA_EXPORT Pipeline : public DemuxerHost {
   // Callback executed by filters to update statistics.
   void OnUpdateStatistics(const PipelineStatistics& stats);
 
-  // Callback executed by audio renderer to update clock time.
-  void OnAudioTimeUpdate(base::TimeDelta time, base::TimeDelta max_time);
-
-  // Callback executed by video renderer to update clock time.
-  void OnVideoTimeUpdate(base::TimeDelta max_time);
-
   // The following "task" methods correspond to the public methods, but these
   // methods are run as the result of posting a task to the Pipeline's
   // task runner.
@@ -317,9 +311,6 @@ class MEDIA_EXPORT Pipeline : public DemuxerHost {
   void PausePlayback();
   void StartPlayback();
 
-  void PauseClockAndStopRendering_Locked();
-  void StartClockIfWaitingForTimeUpdate_Locked();
-
   // Task runner used to execute pipeline tasks.
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
@@ -352,26 +343,6 @@ class MEDIA_EXPORT Pipeline : public DemuxerHost {
   // Current duration as reported by |demuxer_|.
   base::TimeDelta duration_;
 
-  // base::TickClock used by |interpolator_|.
-  base::DefaultTickClock default_tick_clock_;
-
-  // Tracks the most recent media time update and provides interpolated values
-  // as playback progresses.
-  scoped_ptr<TimeDeltaInterpolator> interpolator_;
-
-  enum InterpolationState {
-    // Audio (if present) is not rendering. Time isn't being interpolated.
-    INTERPOLATION_STOPPED,
-
-    // Audio (if present) is rendering. Time isn't being interpolated.
-    INTERPOLATION_WAITING_FOR_AUDIO_TIME_UPDATE,
-
-    // Audio (if present) is rendering. Time is being interpolated.
-    INTERPOLATION_STARTED,
-  };
-
-  InterpolationState interpolation_state_;
-
   // Status of the pipeline.  Initialized to PIPELINE_OK which indicates that
   // the pipeline is operating correctly. Any other value indicates that the
   // pipeline is stopped or is stopping.  Clients can call the Stop() method to
@@ -420,6 +391,9 @@ class MEDIA_EXPORT Pipeline : public DemuxerHost {
   scoped_ptr<VideoRenderer> video_renderer_;
   scoped_ptr<TextRenderer> text_renderer_;
 
+  TimeSource* time_source_;
+  scoped_ptr<WallClockTimeSource> wall_clock_time_source_;
+
   PipelineStatistics statistics_;
 
   scoped_ptr<SerialRunner> pending_callbacks_;