cc: Track BeginMainFrame more precisely in CompositorTimingHistory.

cc/trees/channel_main.h

Index: cc/trees/channel_main.h
diff --git a/cc/trees/channel_main.h b/cc/trees/channel_main.h
index 9c6689c1c4f4c6f9e993494fa725472e06df1046..8f8c4ee99ca6e188d001ed5cb2fb4524460bbbb6 100644
--- a/cc/trees/channel_main.h
+++ b/cc/trees/channel_main.h
@@ -43,9 +43,12 @@ class CC_EXPORT ChannelMain {
       bool* main_frame_will_happen) = 0;
   virtual void SetNeedsRedrawOnImpl(const gfx::Rect& damage_rect) = 0;
   virtual void SetNeedsCommitOnImpl() = 0;
-  virtual void BeginMainFrameAbortedOnImpl(CommitEarlyOutReason reason) = 0;
+  virtual void BeginMainFrameAbortedOnImpl(
+      CommitEarlyOutReason reason,
+      base::TimeTicks main_thread_start_time) = 0;
   virtual void StartCommitOnImpl(CompletionEvent* completion,
                                  LayerTreeHost* layer_tree_host,
+                                 base::TimeTicks main_thread_start_time,
                                  bool hold_commit_for_activation) = 0;
   virtual void InitializeImplOnImpl(CompletionEvent* completion,
                                     LayerTreeHost* layer_tree_host) = 0;