Change the TimeSource interface to return wallclock time for video.

media/base/wall_clock_time_source.cc

Index: media/base/wall_clock_time_source.cc
diff --git a/media/base/wall_clock_time_source.cc b/media/base/wall_clock_time_source.cc
index 408de93e05e830867278d3e667bc3ff4ad59abb2..44491da410f7d1c8d91a1c04e6faa4f65fae4795 100644
--- a/media/base/wall_clock_time_source.cc
+++ b/media/base/wall_clock_time_source.cc
@@ -6,6 +6,7 @@
 
 #include "base/logging.h"
 #include "base/time/default_tick_clock.h"
+#include "media/base/buffers.h"

[xhwang, 2015/03/23 22:20:14]

not needed?

BTW, media/base/buffers.h should be renamed or cleaned...

[DaleCurtis, 2015/03/25 00:31:45]

Done.

 
 namespace media {
 
@@ -60,8 +61,15 @@ base::TimeDelta WallClockTimeSource::CurrentMediaTime() {
   return CurrentMediaTime_Locked();
 }
 
-base::TimeDelta WallClockTimeSource::CurrentMediaTimeForSyncingVideo() {
-  return CurrentMediaTime();
+base::TimeTicks WallClockTimeSource::GetWallclockTimeForMediaTime(
+    base::TimeDelta time) {
+  base::AutoLock auto_lock(lock_);
+  if (!ticking_ || playback_rate_ == 0.0 || time < base_time_)

[xhwang, 2015/03/23 22:20:14]

Can we do DCHECK(time >= base_time_)?

[DaleCurtis, 2015/03/25 00:31:45]

Actually this condition was incorrect, it needs to support time < base_time_ if
playback rate changes yet the frame is still in the queue for some reason.

[xhwang, 2015/03/25 04:10:50]

Acknowledged.

+    return base::TimeTicks();
+
+  return reference_wall_ticks_ +
+         base::TimeDelta::FromMicroseconds(
+             (time - base_time_).InMicroseconds() * playback_rate_);
 }
 
 void WallClockTimeSource::SetTickClockForTesting(