Revert of cc: Remove frame queuing from the scheduler. (patchset #14 id:400001 of https://coderevie…

cc/scheduler/scheduler.h

Index: cc/scheduler/scheduler.h
diff --git a/cc/scheduler/scheduler.h b/cc/scheduler/scheduler.h
index 2ba1f20da1f314a04d3e938cdec21a634ed3f093..57470da922e0021a0dc9a6662c58fa25ff51249a 100644
--- a/cc/scheduler/scheduler.h
+++ b/cc/scheduler/scheduler.h
@@ -150,14 +150,16 @@ class CC_EXPORT Scheduler : public BeginFrameObserverBase {
 
   std::unique_ptr<CompositorTimingHistory> compositor_timing_history_;
 
+  std::deque<BeginFrameArgs> begin_retro_frame_args_;
   SchedulerStateMachine::BeginImplFrameDeadlineMode
       begin_impl_frame_deadline_mode_;
   BeginFrameTracker begin_impl_frame_tracker_;
   BeginFrameArgs begin_main_frame_args_;
 
+  base::Closure begin_retro_frame_closure_;
   base::Closure begin_impl_frame_deadline_closure_;
+  base::CancelableClosure begin_retro_frame_task_;
   base::CancelableClosure begin_impl_frame_deadline_task_;
-  base::CancelableClosure missed_begin_frame_task_;
 
   SchedulerStateMachine state_machine_;
   bool inside_process_scheduled_actions_;
@@ -168,6 +170,7 @@ class CC_EXPORT Scheduler : public BeginFrameObserverBase {
   void ScheduleBeginImplFrameDeadlineIfNeeded();
   void BeginImplFrameNotExpectedSoon();
   void SetupNextBeginFrameIfNeeded();
+  void PostBeginRetroFrameIfNeeded();
   void DrawAndSwapIfPossible();
   void DrawAndSwapForced();
   void ProcessScheduledActions();
@@ -181,6 +184,7 @@ class CC_EXPORT Scheduler : public BeginFrameObserverBase {
       base::TimeDelta bmf_to_activate_estimate) const;
   void AdvanceCommitStateIfPossible();
   bool IsBeginMainFrameSentOrStarted() const;
+  void BeginRetroFrame();
   void BeginImplFrameWithDeadline(const BeginFrameArgs& args);
   void BeginImplFrameSynchronous(const BeginFrameArgs& args);
   void BeginImplFrame(const BeginFrameArgs& args);