Revert of cc: Remove frame queuing from the scheduler.

cc/trees/proxy_impl.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/proxy_impl.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 82 matching lines @@
 
 ProxyImpl::BlockedMainCommitOnly::~BlockedMainCommitOnly() {}
 
 ProxyImpl::~ProxyImpl() {
   TRACE_EVENT0("cc", "ProxyImpl::~ProxyImpl");
   DCHECK(IsImplThread());
   DCHECK(IsMainThreadBlocked());
 
   // 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();
+
   scheduler_ = nullptr;
   external_begin_frame_source_ = nullptr;
   layer_tree_host_impl_ = nullptr;
   // We need to explicitly shutdown the notifier to destroy any weakptrs it is
   // holding while still on the compositor thread. This also ensures any
   // callbacks holding a ProxyImpl pointer are cancelled.
   smoothness_priority_expiration_notifier_.Shutdown();
 }
 
 void ProxyImpl::InitializeMutatorOnImpl(
@@ skipping 496 matching lines @@
 bool ProxyImpl::IsMainThreadBlocked() const {
   return task_runner_provider_->IsMainThreadBlocked();
 }
 
 ProxyImpl::BlockedMainCommitOnly& ProxyImpl::blocked_main_commit() {
   DCHECK(IsMainThreadBlocked() && commit_completion_event_);
   return main_thread_blocked_commit_vars_unsafe_;
 }
 
 }  // namespace cc