cc: Send BeginFrame to VideoFrameController when added if we're inside a frame.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index c90087641c359b49dec6150e13fb4196a0eeed4c..59e59fa0cbee31c3b7a4a6631c144a6932c3f051 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -3084,6 +3084,8 @@ void LayerTreeHostImpl::AddVideoFrameController(
     VideoFrameController* controller) {
   bool was_empty = video_frame_controllers_.empty();
   video_frame_controllers_.insert(controller);
+  if (current_begin_frame_args_.IsValid())
+    controller->OnBeginFrame(current_begin_frame_args_);

[brianderson, 2015/05/04 23:39:47]

Not that the controller is really going to care, but should we set the type to
MISSED before forwarding it to the controller?

Fine with holding off on this until the controller actually wants to use it.
Especially since we'd get this for free if/when the BeginFrameSource supports
multiple subscribers.

[sunnyps, 2015/05/04 23:41:06]

Yeah, let's hold off on this until we need it.

   if (was_empty)
     client_->SetVideoNeedsBeginFrames(true);
 }