Update from https://crrev.com/304121

cc/debug/rendering_stats_instrumentation.cc

Index: cc/debug/rendering_stats_instrumentation.cc
diff --git a/cc/debug/rendering_stats_instrumentation.cc b/cc/debug/rendering_stats_instrumentation.cc
index f5f2e07225decba492f42d79369887a5345376cb..c707e233c608b4e603595c7660409b14b453b9b0 100644
--- a/cc/debug/rendering_stats_instrumentation.cc
+++ b/cc/debug/rendering_stats_instrumentation.cc
@@ -18,14 +18,7 @@ RenderingStatsInstrumentation::RenderingStatsInstrumentation()
 
 RenderingStatsInstrumentation::~RenderingStatsInstrumentation() {}
 
-RenderingStats::MainThreadRenderingStats
-RenderingStatsInstrumentation::main_thread_rendering_stats() {
-  base::AutoLock scoped_lock(lock_);
-  return main_thread_rendering_stats_;
-}
-
-RenderingStats::ImplThreadRenderingStats
-RenderingStatsInstrumentation::impl_thread_rendering_stats() {
+RenderingStats RenderingStatsInstrumentation::impl_thread_rendering_stats() {
   base::AutoLock scoped_lock(lock_);
   return impl_thread_rendering_stats_;
 }
@@ -33,23 +26,15 @@ RenderingStatsInstrumentation::impl_thread_rendering_stats() {
 RenderingStats RenderingStatsInstrumentation::GetRenderingStats() {
   base::AutoLock scoped_lock(lock_);
   RenderingStats rendering_stats;
-  rendering_stats.main_stats = main_thread_rendering_stats_accu_;
-  rendering_stats.main_stats.Add(main_thread_rendering_stats_);
-  rendering_stats.impl_stats = impl_thread_rendering_stats_accu_;
-  rendering_stats.impl_stats.Add(impl_thread_rendering_stats_);
+  rendering_stats = impl_thread_rendering_stats_accu_;
+  rendering_stats.Add(impl_thread_rendering_stats_);
   return rendering_stats;
 }
 
-void RenderingStatsInstrumentation::AccumulateAndClearMainThreadStats() {
-  base::AutoLock scoped_lock(lock_);
-  main_thread_rendering_stats_accu_.Add(main_thread_rendering_stats_);
-  main_thread_rendering_stats_ = RenderingStats::MainThreadRenderingStats();
-}
-
 void RenderingStatsInstrumentation::AccumulateAndClearImplThreadStats() {
   base::AutoLock scoped_lock(lock_);
   impl_thread_rendering_stats_accu_.Add(impl_thread_rendering_stats_);
-  impl_thread_rendering_stats_ = RenderingStats::ImplThreadRenderingStats();
+  impl_thread_rendering_stats_ = RenderingStats();
 }
 
 base::TimeTicks RenderingStatsInstrumentation::StartRecording() const {
@@ -79,26 +64,6 @@ void RenderingStatsInstrumentation::IncrementFrameCount(int64 count) {
   impl_thread_rendering_stats_.frame_count += count;
 }
 
-void RenderingStatsInstrumentation::AddPaint(base::TimeDelta duration,
-                                             int64 pixels) {
-  if (!record_rendering_stats_)
-    return;
-
-  base::AutoLock scoped_lock(lock_);
-  main_thread_rendering_stats_.paint_time += duration;
-  main_thread_rendering_stats_.painted_pixel_count += pixels;
-}
-
-void RenderingStatsInstrumentation::AddRecord(base::TimeDelta duration,
-                                              int64 pixels) {
-  if (!record_rendering_stats_)
-    return;
-
-  base::AutoLock scoped_lock(lock_);
-  main_thread_rendering_stats_.record_time += duration;
-  main_thread_rendering_stats_.recorded_pixel_count += pixels;
-}
-
 void RenderingStatsInstrumentation::AddVisibleContentArea(int64 area) {
   if (!record_rendering_stats_)
     return;