cc:: Add RenderingStatsInstrumentation to manage collection of RenderingStats

cc/thread_proxy.cc

Index: cc/thread_proxy.cc
diff --git a/cc/thread_proxy.cc b/cc/thread_proxy.cc
index 41d6d90e8dbc3bbbac7ee03a084431df85d8912e..da2555c38459b2ea9574759cf8069ff5bcf47a88 100644
--- a/cc/thread_proxy.cc
+++ b/cc/thread_proxy.cc
@@ -60,7 +60,6 @@ ThreadProxy::ThreadProxy(LayerTreeHost* layer_tree_host,
       next_frame_is_newly_committed_frame_on_impl_thread_(false),
       render_vsync_enabled_(layer_tree_host->settings().renderVSyncEnabled),
       inside_draw_(false),
-      total_commit_count_(0),
       defer_commits_(false),
       renew_tree_priority_on_impl_thread_pending_(false) {
   TRACE_EVENT0("cc", "ThreadProxy::ThreadProxy");
@@ -278,22 +277,6 @@ bool ThreadProxy::RecreateOutputSurface() {
   return recreate_succeeded;
 }
 
-void ThreadProxy::CollectRenderingStats(RenderingStats* stats) {
-  DCHECK(IsMainThread());
-
-  DebugScopedSetMainThreadBlocked main_thread_blocked(this);
-  CompletionEvent completion;
-  Proxy::ImplThread()->postTask(
-      base::Bind(&ThreadProxy::RenderingStatsOnImplThread,
-                 impl_thread_weak_ptr_,
-                 &completion,
-                 stats));
-  stats->totalCommitTime = total_commit_time_;
-  stats->totalCommitCount = total_commit_count_;
-
-  completion.wait();
-}
-
 const RendererCapabilities& ThreadProxy::GetRendererCapabilities() const {
   DCHECK(renderer_initialized_);
   return renderer_capabilities_main_thread_copy_;
@@ -743,9 +726,12 @@ void ThreadProxy::BeginFrame(
   {
     TRACE_EVENT0("cc", "commit");
 
-    DebugScopedSetMainThreadBlocked main_thread_blocked(this);
+    DebugScopedSetMainThreadBlocked main_thread_blocked(this); 
+
+    RenderingStatsInstrumentation* stats_instrumentation =
+        layer_tree_host_->rendering_stats_instrumentation();
+    base::TimeTicks start_time = stats_instrumentation->StartRecording();
 
-    base::TimeTicks start_time = base::TimeTicks::HighResNow();
     CompletionEvent completion;
     Proxy::ImplThread()->postTask(
         base::Bind(&ThreadProxy::BeginFrameCompleteOnImplThread,
@@ -755,9 +741,8 @@ void ThreadProxy::BeginFrame(
                    offscreen_context_provider));
     completion.wait();
 
-    base::TimeTicks end_time = base::TimeTicks::HighResNow();
-    total_commit_time_ += end_time - start_time;
-    total_commit_count_++;
+    base::TimeDelta duration = stats_instrumentation->EndRecording(start_time);
+    stats_instrumentation->AddCommit(duration);
   }
 
   layer_tree_host_->CommitComplete();
@@ -1178,13 +1163,6 @@ void ThreadProxy::RecreateOutputSurfaceOnImplThread(
   completion->signal();
 }
 
-void ThreadProxy::RenderingStatsOnImplThread(CompletionEvent* completion,
-                                             RenderingStats* stats) {
-  DCHECK(IsImplThread());
-  layer_tree_host_impl_->CollectRenderingStats(stats);
-  completion->signal();
-}
-
 ThreadProxy::BeginFrameAndCommitState::BeginFrameAndCommitState()
     : memory_allocation_limit_bytes(0) {}