Scheduler: Switch from high to low latency mode if possible.

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 <string>
 
 #include "base/basictypes.h"
@@ skipping 84 matching lines @@
   void DidCreateAndInitializeOutputSurface();
   bool HasInitializedOutputSurface() const {
     return state_machine_.HasInitializedOutputSurface();
   }
 
   bool CommitPending() const { return state_machine_.CommitPending(); }
   bool RedrawPending() const { return state_machine_.RedrawPending(); }
   bool ManageTilesPending() const {
     return state_machine_.ManageTilesPending();
   }
+  bool MainThreadIsInHighLatencyMode() const {
+    return state_machine_.MainThreadIsInHighLatencyMode();
+  }
 
   bool WillDrawIfNeeded() const;
 
   base::TimeTicks AnticipatedDrawTime();
 
   base::TimeTicks LastBeginImplFrameTime();
 
   void BeginImplFrame(const BeginFrameArgs& args);
   void OnBeginImplFrameDeadline();
   void PollForAnticipatedDrawTriggers();
@@ skipping 11 matching lines @@
             const SchedulerSettings& scheduler_settings);
 
   void PostBeginImplFrameDeadline(base::TimeTicks deadline);
   void SetupNextBeginImplFrameIfNeeded();
   void ActivatePendingTree();
   void DrawAndSwapIfPossible();
   void DrawAndSwapForced();
   void DrawAndReadback();
   void ProcessScheduledActions();
 
+  bool CanCommitAndActivateBeforeDeadline() const;
+
   const SchedulerSettings settings_;
   SchedulerClient* client_;
 
   bool last_set_needs_begin_impl_frame_;
   BeginFrameArgs last_begin_impl_frame_args_;
   base::CancelableClosure begin_impl_frame_deadline_closure_;
   base::CancelableClosure poll_for_draw_triggers_closure_;
 
   SchedulerStateMachine state_machine_;
   bool inside_process_scheduled_actions_;
   SchedulerStateMachine::Action inside_action_;
 
   base::WeakPtrFactory<Scheduler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Scheduler);
 };
 
 }  // namespace cc
 
 #endif  // CC_SCHEDULER_SCHEDULER_H_