Reland of cc: Remove frame queuing from the scheduler.

cc/trees/proxy_impl.cc

Index: cc/trees/proxy_impl.cc
diff --git a/cc/trees/proxy_impl.cc b/cc/trees/proxy_impl.cc
index 64697d7b0dcc7bd4fbf13f4b55a1e3cd7bb75f30..72f6207f7121dac76f2ed5bc6dfde59b973a456c 100644
--- a/cc/trees/proxy_impl.cc
+++ b/cc/trees/proxy_impl.cc
@@ -100,9 +100,7 @@ ProxyImpl::~ProxyImpl() {
 
   // Take away the CompositorFrameSink before destroying things so it doesn't
   // try to call into its client mid-shutdown.
-  scheduler_->DidLoseCompositorFrameSink();
   layer_tree_host_impl_->ReleaseCompositorFrameSink();

[enne (OOO), 2016/09/21 17:38:55]

It's a little odd that single thread proxy now calls did lose compositor frame
sink but proxy impl doesn't.  Does this cause any issues?  Should the single
thread proxy one not do that as well?

[sunnyps, 2016/09/24 01:15:01]

This is LTHI::ReleaseCFS not Scheduler::DidLoseCFS which was removed. Both STP
and ProxyImpl only call ReleaseCFS. There's no need to call DidLoseCFS because
the scheduler isn't expected to do anything at this point.

-
   scheduler_ = nullptr;
   external_begin_frame_source_ = nullptr;
   layer_tree_host_impl_ = nullptr;