Use ThreadNow() for recording times.

cc/debug/rendering_stats_instrumentation.cc

 // Copyright 2013 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/debug/rendering_stats_instrumentation.h"
 
 namespace cc {
 
 // static
 scoped_ptr<RenderingStatsInstrumentation>
@@ skipping 21 matching lines @@
   main_stats_accu_.Add(main_stats_);
   main_stats_ = MainThreadRenderingStats();
 }
 
 void RenderingStatsInstrumentation::AccumulateAndClearImplThreadStats() {
   impl_stats_accu_.Add(impl_stats_);
   impl_stats_ = ImplThreadRenderingStats();
 }
 
 base::TimeTicks RenderingStatsInstrumentation::StartRecording() const {
-  if (record_rendering_stats_)
+  if (record_rendering_stats_) {
+    if (base::TimeTicks::IsThreadNowSupported())
+      return base::TimeTicks::ThreadNow();
     return base::TimeTicks::HighResNow();
+  }
   return base::TimeTicks();
 }
 
 base::TimeDelta RenderingStatsInstrumentation::EndRecording(
     base::TimeTicks start_time) const {
-  if (!start_time.is_null())
+  if (!start_time.is_null()) {
+    if (base::TimeTicks::IsThreadNowSupported())
+      return base::TimeTicks::ThreadNow() - start_time;
     return base::TimeTicks::HighResNow() - start_time;
+  }
   return base::TimeDelta();
 }
 
 void RenderingStatsInstrumentation::IncrementAnimationFrameCount() {
   if (!record_rendering_stats_)
     return;
 
   base::AutoLock scoped_lock(lock_);
   main_stats_.animation_frame_count++;
 }
@@ skipping 132 matching lines @@
     return;
 
   base::AutoLock scoped_lock(lock_);
   impl_stats_.tile_analysis_count++;
   impl_stats_.tile_analysis_time += duration;
   if (is_solid_color)
     impl_stats_.solid_color_tile_analysis_count++;
 }
 
 }  // namespace cc