Add tracing AutoOpenCloseEvent.

media/blink/video_frame_compositor.h

Index: media/blink/video_frame_compositor.h
diff --git a/media/blink/video_frame_compositor.h b/media/blink/video_frame_compositor.h
index 9bb79fd056a9651221652435bc2ca29103973661..309b543028f837fa83349bda802a5ae3667a9870 100644
--- a/media/blink/video_frame_compositor.h
+++ b/media/blink/video_frame_compositor.h
@@ -14,6 +14,7 @@
 #include "base/synchronization/lock.h"
 #include "base/time/tick_clock.h"
 #include "base/timer/timer.h"
+#include "base/trace_event/video_playback_pae.h"
 #include "cc/layers/video_frame_provider.h"
 #include "media/base/video_renderer_sink.h"
 #include "media/blink/media_blink_export.h"
@@ -160,6 +161,9 @@ class MEDIA_BLINK_EXPORT VideoFrameCompositor
   base::Lock callback_lock_;
   VideoRendererSink::RenderCallback* callback_;
 
+  // Persistent async event
+  base::trace_event::VideoPlaybackPersistentAsyncEvent* persistent_async_;

[DaleCurtis, 2016/08/29 21:43:15]

Seems like this should be an std::unique_ptr<> unless you're intending Stop() to
self-delete.

[alexandermont, 2016/08/30 19:01:22]

Done

+
   DISALLOW_COPY_AND_ASSIGN(VideoFrameCompositor);
 };