cc: Measure compositor timing with finer granularity

cc/trees/layer_tree_host_impl_unittest.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/layer_tree_host_impl.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/bind.h"
@@ skipping 138 matching lines @@
     return reduce_memory_result_;
   }
   bool IsInsideDraw() override { return false; }
   void RenewTreePriority() override {}
   void PostDelayedAnimationTaskOnImplThread(const base::Closure& task,
                                             base::TimeDelta delay) override {
     animation_task_ = task;
     requested_animation_delay_ = delay;
   }
   void DidActivateSyncTree() override {}
+  void WillPrepareTiles() override {}
   void DidPrepareTiles() override {}
   void DidCompletePageScaleAnimationOnImplThread() override {
     did_complete_page_scale_animation_ = true;
   }
   void OnDrawForOutputSurface() override {}
   void PostFrameTimingEventsOnImplThread(
       scoped_ptr<FrameTimingTracker::CompositeTimingSet> composite_events,
       scoped_ptr<FrameTimingTracker::MainFrameTimingSet> main_frame_events)
       override {}
 
@@ skipping 7872 matching lines @@
   // Hold an unowned pointer to the output surface to use for mock expectations.
   MockReclaimResourcesOutputSurface* mock_output_surface = output_surface.get();
 
   CreateHostImpl(DefaultSettings(), output_surface.Pass());
   EXPECT_CALL(*mock_output_surface, ForceReclaimResources()).Times(1);
   host_impl_->BeginCommit();
 }
 
 }  // namespace
 }  // namespace cc