[cc]: Add a BeginMainFrameNotExpectedSoon signal and route it to the RendererScheduler.

cc/scheduler/scheduler.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_SCHEDULER_SCHEDULER_H_
 #define CC_SCHEDULER_SCHEDULER_H_
 
 #include <deque>
 #include <string>
 
@@ skipping 31 matching lines @@
   virtual void ScheduledActionCommit() = 0;
   virtual void ScheduledActionActivateSyncTree() = 0;
   virtual void ScheduledActionBeginOutputSurfaceCreation() = 0;
   virtual void ScheduledActionPrepareTiles() = 0;
   virtual void DidAnticipatedDrawTimeChange(base::TimeTicks time) = 0;
   virtual base::TimeDelta DrawDurationEstimate() = 0;
   virtual base::TimeDelta BeginMainFrameToCommitDurationEstimate() = 0;
   virtual base::TimeDelta CommitToActivateDurationEstimate() = 0;
   virtual void DidBeginImplFrameDeadline() = 0;
   virtual void SendBeginFramesToChildren(const BeginFrameArgs& args) = 0;
+  virtual void SendBeginMainFrameNoLongerRequired() = 0;
 
  protected:
   virtual ~SchedulerClient() {}
 };
 
 class Scheduler;
 // This class exists to allow tests to override the frame source construction.
 // A virtual method can't be used as this needs to happen in the constructor
 // (see C++ FAQ / Section 23 - http://goo.gl/fnrwom for why).
 // This class exists solely long enough to construct the frame sources.
@@ skipping 196 matching lines @@
 
   friend class SchedulerFrameSourcesConstructor;
   friend class TestSchedulerFrameSourcesConstructor;
 
   DISALLOW_COPY_AND_ASSIGN(Scheduler);
 };
 
 }  // namespace cc
 
 #endif  // CC_SCHEDULER_SCHEDULER_H_