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

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 582 matching lines @@
 
   DrawResult result;
   if (layer_tree_host_impl_->CanDraw()) {
     result = layer_tree_host_impl_->PrepareToDraw(&frame);
     draw_frame = forced_draw || result == DRAW_SUCCESS;
   } else {
     result = DRAW_ABORTED_CANT_DRAW;
   }
 
   if (draw_frame) {
-    layer_tree_host_impl_->DrawLayers(&frame);
-    if (layer_tree_host_impl_->SwapBuffers(frame))
+    if (layer_tree_host_impl_->DrawLayers(&frame))
       scheduler_->DidSwapBuffers();
     result = DRAW_SUCCESS;
   } else {
     DCHECK_NE(DRAW_SUCCESS, result);
   }
 
   layer_tree_host_impl_->DidDrawAllLayers(frame);
 
   bool start_ready_animations = draw_frame;
   layer_tree_host_impl_->UpdateAnimationState(start_ready_animations);
@@ skipping 15 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