cc: Track BeginMainFrame more precisely in CompositorTimingHistory.

cc/scheduler/compositor_timing_history_unittest.cc

Index: cc/scheduler/compositor_timing_history_unittest.cc
diff --git a/cc/scheduler/compositor_timing_history_unittest.cc b/cc/scheduler/compositor_timing_history_unittest.cc
index 5ffd68e95d2a3ce3ee4faf6dd36191ffcd08da43..e3ea3b6cb14cf98d16faded487fb133dea3d36d6 100644
--- a/cc/scheduler/compositor_timing_history_unittest.cc
+++ b/cc/scheduler/compositor_timing_history_unittest.cc
@@ -63,7 +63,8 @@ TEST_F(CompositorTimingHistoryTest, AllSequentialCommit) {
   base::TimeDelta activate_duration = base::TimeDelta::FromMilliseconds(4);
   base::TimeDelta draw_duration = base::TimeDelta::FromMilliseconds(5);
 
-  timing_history_.WillBeginMainFrame();
+  timing_history_.WillBeginMainFrame(false);
+  timing_history_.BeginMainFrameStarted(Now());
   AdvanceNowBy(begin_main_frame_to_commit_duration);
   // timing_history_.BeginMainFrameAborted();
   timing_history_.DidCommit();
@@ -106,7 +107,8 @@ TEST_F(CompositorTimingHistoryTest, AllSequentialBeginMainFrameAborted) {
   base::TimeDelta activate_duration = base::TimeDelta::FromMilliseconds(4);
   base::TimeDelta draw_duration = base::TimeDelta::FromMilliseconds(5);
 
-  timing_history_.WillBeginMainFrame();
+  timing_history_.WillBeginMainFrame(false);
+  timing_history_.BeginMainFrameStarted(Now());
   AdvanceNowBy(begin_main_frame_to_commit_duration);
   // BeginMainFrameAborted counts as a commit complete.
   timing_history_.BeginMainFrameAborted();