HW Video: Make media::VideoFrame handle the sync point of the compositor as well as webgl

content/browser/renderer_host/media/video_capture_controller.cc

Index: content/browser/renderer_host/media/video_capture_controller.cc
diff --git a/content/browser/renderer_host/media/video_capture_controller.cc b/content/browser/renderer_host/media/video_capture_controller.cc
index f625a0732c06f9f9c59cad2282d83933d3d6b524..1fc30dbf17967c4f7515be2294c475678e9a9a35 100644
--- a/content/browser/renderer_host/media/video_capture_controller.cc
+++ b/content/browser/renderer_host/media/video_capture_controller.cc
@@ -251,7 +251,7 @@ void VideoCaptureController::ReturnBuffer(
     const VideoCaptureControllerID& id,
     VideoCaptureControllerEventHandler* event_handler,
     int buffer_id,
-    uint32 sync_point) {
+    const std::vector<uint32>& sync_points) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   ControllerClient* client = FindClient(id, event_handler, controller_clients_);
@@ -267,8 +267,10 @@ void VideoCaptureController::ReturnBuffer(
   scoped_refptr<media::VideoFrame> frame = iter->second;
   client->active_buffers.erase(iter);
 
-  if (frame->format() == media::VideoFrame::NATIVE_TEXTURE)
-    frame->mailbox_holder()->sync_point = sync_point;
+  if (frame->format() == media::VideoFrame::NATIVE_TEXTURE) {
+    for (size_t i = 0; i < sync_points.size(); i++)
+      frame->AppendReleaseSyncPoint(sync_points[i]);

[danakj, 2014/03/20 15:59:08]

Do you know where is the callback that will eventually receive these sync
points? I'm trying to follow this back, but the VideoFrames I see are:

https://code.google.com/p/chromium/codesearch#chromium/src/content/browser/re...

and 

https://code.google.com/p/chromium/codesearch#chromium/src/content/browser/me...

which are both WrapExternalPackedMemory. I'm failing to see how a native texture
frame would end up here.

[dshwang, 2014/03/20 16:11:20]

That's good question. AFAIK, currently VidoeCaptureController don't create
NATIVE_TEXTURE VideoFrame. It means this code exist just for future.
Ami, jln@, am I right?

[Ami GONE FROM CHROMIUM, 2014/04/11 20:55:17]

Yep.

+  }
 
   buffer_pool_->RelinquishConsumerHold(buffer_id, 1);
 }