cc: Merge the DrawLayer()/DrawFrame() and SwapBuffers() methods.

cc/trees/single_thread_proxy.cc

 // 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.
 
 #include "cc/trees/single_thread_proxy.h"
 
 #include "base/auto_reset.h"
 #include "base/memory/ptr_util.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 555 matching lines @@
     // the DidCommitAndDrawFrame() must be post-tasked from the impl thread
     // there as the main thread is not blocked, so any posted tasks inside
     // the swap buffers will execute first.
     DebugScopedSetMainThreadBlocked main_thread_blocked(task_runner_provider_);
     BlockingTaskRunner::CapturePostTasks blocked(
         task_runner_provider_->blocking_main_thread_task_runner());
 
     draw_result = layer_tree_host_impl_->PrepareToDraw(frame);
     draw_frame = draw_result == DRAW_SUCCESS;
     if (draw_frame) {
-      layer_tree_host_impl_->DrawLayers(frame);
-      if (layer_tree_host_impl_->SwapBuffers(*frame)) {
+      if (layer_tree_host_impl_->DrawLayers(frame)) {
         if (scheduler_on_impl_thread_)
           scheduler_on_impl_thread_->DidSwapBuffers();
         client_->DidPostSwapBuffers();
       }
     }
     layer_tree_host_impl_->DidDrawAllLayers(*frame);
 
     bool start_ready_animations = draw_frame;
     layer_tree_host_impl_->UpdateAnimationState(start_ready_animations);
   }
@@ skipping 179 matching lines @@
 void SingleThreadProxy::DidFinishImplFrame() {
   layer_tree_host_impl_->DidFinishImplFrame();
 #if DCHECK_IS_ON()
   DCHECK(inside_impl_frame_)
       << "DidFinishImplFrame called while not inside an impl frame!";
   inside_impl_frame_ = false;
 #endif
 }
 
 }  // namespace cc