Add WebMediaPlayer::timelineOffset() support to WebMediaPlayerImpl.

media/base/demuxer.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_DEMUXER_H_
 #define MEDIA_BASE_DEMUXER_H_
 
 #include <vector>
 
 #include "base/time/time.h"
@@ skipping 69 matching lines @@
   // TODO(scherkus): this might not be needed http://crbug.com/234708
   virtual void OnAudioRendererDisabled() = 0;
 
   // Returns the first stream of the given stream type (which is not allowed
   // to be DemuxerStream::TEXT), or NULL if that type of stream is not present.
   virtual DemuxerStream* GetStream(DemuxerStream::Type type) = 0;
 
   // Returns the starting time for the media file.
   virtual base::TimeDelta GetStartTime() const = 0;
 
+  // Returns wallclock time represented by presentation timestamp 0.

[scherkus (not reviewing), 2014/04/15 00:53:40]

isn't it "wall clock" with a space, as in a clock that is on the wall?

also it's interesting that you use timeline_offset_ in numerous places without
the wallclock_ prefix, but have functions that do have Wallclock in there

how about side-stepping this whole bit by removing the words "wall clock"
everywhere since base::Time is by definition a wall clock time? (see
base/time/time.h)

[acolwell GONE FROM CHROMIUM, 2014/04/16 01:01:08]

Done.

+  // If the timstamps are not associated with a wallclock time, then
+  // a null Time is returned.
+  virtual base::Time GetWallclockTimelineOffset() const = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(Demuxer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_DEMUXER_H_