Update from https://crrev.com/314320

cc/trees/single_thread_proxy.h

 // Copyright 2011 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.
 
 #ifndef CC_TREES_SINGLE_THREAD_PROXY_H_
 #define CC_TREES_SINGLE_THREAD_PROXY_H_
 
 #include <limits>
 
 #include "base/cancelable_callback.h"
@@ skipping 96 matching lines @@
   void DidActivateSyncTree() override;
   void DidPrepareTiles() override;
   void DidCompletePageScaleAnimationOnImplThread() override;
   void SetDebugState(const LayerTreeDebugState& debug_state) override {}
 
   void RequestNewOutputSurface();
 
   // Called by the legacy path where RenderWidget does the scheduling.
   void CompositeImmediately(base::TimeTicks frame_begin_time);
 
- private:
+ protected:
   SingleThreadProxy(
       LayerTreeHost* layer_tree_host,
       LayerTreeHostSingleThreadClient* client,
       scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
       scoped_ptr<BeginFrameSource> external_begin_frame_source);
 
+ private:
   void BeginMainFrame();
   void BeginMainFrameAbortedOnImplThread(CommitEarlyOutReason reason);
   void DoAnimate();
   void DoBeginMainFrame(const BeginFrameArgs& begin_frame_args);
   void DoCommit();
   DrawResult DoComposite(base::TimeTicks frame_begin_time,
                          LayerTreeHostImpl::FrameData* frame);
   void DoSwap();
   void DidCommitAndDrawFrame();
   void CommitComplete();
@@ skipping 13 matching lines @@
   // Accessed from both threads.
   scoped_ptr<Scheduler> scheduler_on_impl_thread_;
   ProxyTimingHistory timing_history_;
 
   scoped_ptr<BlockingTaskRunner::CapturePostTasks> commit_blocking_task_runner_;
   scoped_ptr<ResourceUpdateQueue> queue_for_commit_;
   bool next_frame_is_newly_committed_frame_;
 
   bool inside_draw_;
   bool defer_commits_;
-  bool commit_was_deferred_;
   bool commit_requested_;
   bool inside_synchronous_composite_;
 
   // True if a request to the LayerTreeHostClient to create an output surface
   // is still outstanding.
   bool output_surface_creation_requested_;
 
   // This is the callback for the scheduled RequestNewOutputSurface.
   base::CancelableClosure output_surface_creation_callback_;
 
@@ skipping 61 matching lines @@
  private:
   DebugScopedSetImplThread impl_thread_;
   DebugScopedSetMainThreadBlocked main_thread_blocked_;
 
   DISALLOW_COPY_AND_ASSIGN(DebugScopedSetImplThreadAndMainThreadBlocked);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_SINGLE_THREAD_PROXY_H_