cc: Update main_thread_missed_last_deadline in aborted draws.

cc/scheduler/scheduler_state_machine.cc

Index: cc/scheduler/scheduler_state_machine.cc
diff --git a/cc/scheduler/scheduler_state_machine.cc b/cc/scheduler/scheduler_state_machine.cc
index b168034c3bb632006ca90dd6c572cb80ca2f67bf..a1314fa495a318f64794145afdf93b98c7e8eee6 100644
--- a/cc/scheduler/scheduler_state_machine.cc
+++ b/cc/scheduler/scheduler_state_machine.cc
@@ -643,6 +643,13 @@ void SchedulerStateMachine::WillActivate() {
 }
 
 void SchedulerStateMachine::WillDrawInternal() {
+  // If a new active tree is pending after the one we are about to draw,
+  // the main thread is in a high latency mode.
+  // main_thread_missed_last_deadline_ is here in addition to
+  // OnBeginImplFrameIdle for cases where the scheduler aborts draws outside
+  // of the deadline.
+  main_thread_missed_last_deadline_ = CommitPending() || has_pending_tree_;
+
   // We need to reset needs_redraw_ before we draw since the
   // draw itself might request another draw.
   needs_redraw_ = false;