cc: Add main frame timing info to frame timing tracker.

cc/trees/thread_proxy.cc

Index: cc/trees/thread_proxy.cc
diff --git a/cc/trees/thread_proxy.cc b/cc/trees/thread_proxy.cc
index 8c766f273da9ab0a291133710fed1a7e10b27968..bd5106f2f395639c0fac4b57f448ee54483b982e 100644
--- a/cc/trees/thread_proxy.cc
+++ b/cc/trees/thread_proxy.cc
@@ -691,6 +691,8 @@ void ThreadProxy::ScheduledActionSendBeginMainFrame() {
       impl().layer_tree_host_impl->memory_allocation_priority_cutoff();
   begin_main_frame_state->evicted_ui_resources =
       impl().layer_tree_host_impl->EvictedUIResourcesExist();
+  impl().layer_tree_host_impl->SetBeginMainFrameTime(

[enne (OOO), 2015/03/10 00:32:29]

Can you rename this to be something other than "BeginMainFrameTime", and tie it
more to like "this value is passed to raf as the current time to animate at"?

[vmpstr, 2015/03/16 18:36:43]

Done.

+      impl().scheduler->LastBeginImplFrameTime());

[mithro-old, 2015/03/11 04:01:33]

What is LastBeginImplFrameTime here?

If it is as enne describes, then it is already stored in
begin_main_frame_state->begin_frame_args

[vmpstr, 2015/03/16 18:36:43]

Done.

   Proxy::MainThreadTaskRunner()->PostTask(
       FROM_HERE,
       base::Bind(&ThreadProxy::BeginMainFrame,
@@ -1394,4 +1396,9 @@ void ThreadProxy::DidCompletePageScaleAnimationOnImplThread() {
                             main_thread_weak_ptr_));
 }
 
+base::TimeTicks ThreadProxy::GetNextBeginImplFrameTimeIfRequested() const {

[mithro-old, 2015/03/11 04:01:33]

What is this used for?

[vmpstr, 2015/03/16 18:36:43]

This plumbs the next predicted raf time to lthi via the client interface.

+  DCHECK(IsImplThread());
+  return impl().scheduler->NextBeginImplFrameTimeIfRequested();
+}
+
 }  // namespace cc