cc: Emulate BeginFrame in OutputSurfaces that don't support it natively

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"
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
 #include "cc/base/cc_export.h"
-#include "cc/scheduler/frame_rate_controller.h"
 #include "cc/scheduler/scheduler_settings.h"
 #include "cc/scheduler/scheduler_state_machine.h"
 #include "cc/trees/layer_tree_host.h"
 
 namespace cc {
 
 class Thread;
 
 struct ScheduledActionDrawAndSwapResult {
   ScheduledActionDrawAndSwapResult()
       : did_draw(false),
         did_swap(false) {}
   ScheduledActionDrawAndSwapResult(bool did_draw, bool did_swap)
       : did_draw(did_draw),
         did_swap(did_swap) {}
   bool did_draw;
   bool did_swap;
 };
 
 class SchedulerClient {
  public:
+  virtual void SetNeedsBeginFrameOnImplThread(bool enable) = 0;
   virtual void ScheduledActionSendBeginFrameToMainThread() = 0;
   virtual ScheduledActionDrawAndSwapResult
   ScheduledActionDrawAndSwapIfPossible() = 0;
   virtual ScheduledActionDrawAndSwapResult
   ScheduledActionDrawAndSwapForced() = 0;
   virtual void ScheduledActionCommit() = 0;
   virtual void ScheduledActionCheckForCompletedTileUploads() = 0;
   virtual void ScheduledActionActivatePendingTreeIfNeeded() = 0;
   virtual void ScheduledActionBeginOutputSurfaceCreation() = 0;
   virtual void ScheduledActionAcquireLayerTexturesForMainThread() = 0;
   virtual void DidAnticipatedDrawTimeChange(base::TimeTicks time) = 0;
 
  protected:
   virtual ~SchedulerClient() {}
 };
 
-class CC_EXPORT Scheduler : FrameRateControllerClient {
+class CC_EXPORT Scheduler {
  public:
   static scoped_ptr<Scheduler> Create(
       SchedulerClient* client,
-      scoped_ptr<FrameRateController> frame_rate_controller,
       const SchedulerSettings& scheduler_settings) {
-    return make_scoped_ptr(new Scheduler(
-        client, frame_rate_controller.Pass(), scheduler_settings));
+    return make_scoped_ptr(new Scheduler(client,  scheduler_settings));
   }
 
   virtual ~Scheduler();
 
   void SetCanStart();
 
   void SetVisible(bool visible);
   void SetCanDraw(bool can_draw);
   void SetHasPendingTree(bool has_pending_tree);
 
   void SetNeedsCommit();
 
   // Like SetNeedsCommit(), but ensures a commit will definitely happen even if
   // we are not visible.
   void SetNeedsForcedCommit();
 
   void SetNeedsRedraw();
 
   void SetMainThreadNeedsLayerTextures();
 
   // Like SetNeedsRedraw(), but ensures the draw will definitely happen even if
   // we are not visible.
   void SetNeedsForcedRedraw();
 
   void DidSwapUseIncompleteTile();
 
   void FinishCommit();
   void BeginFrameAbortedByMainThread();
 
-  void SetMaxFramesPending(int max);
-  int MaxFramesPending() const;
-  int NumFramesPendingForTesting() const;
-
-  void DidSwapBuffersComplete();
-
   void DidLoseOutputSurface();
   void DidCreateAndInitializeOutputSurface();
   bool HasInitializedOutputSurface() const {
     return state_machine_.HasInitializedOutputSurface();
   }
 
   bool CommitPending() const { return state_machine_.CommitPending(); }
   bool RedrawPending() const { return state_machine_.RedrawPending(); }
 
   bool WillDrawIfNeeded() const;
 
-  void SetTimebaseAndInterval(base::TimeTicks timebase,
-                              base::TimeDelta interval);
-
   base::TimeTicks AnticipatedDrawTime();
 
   base::TimeTicks LastBeginFrameOnImplThreadTime();
 
-  // FrameRateControllerClient implementation
-  virtual void BeginFrame(bool throttled) OVERRIDE;
+  void BeginFrame(base::TimeTicks frame_time);
 
   std::string StateAsStringForTesting() { return state_machine_.ToString(); }
 
  private:
   Scheduler(SchedulerClient* client,
-            scoped_ptr<FrameRateController> frame_rate_controller,
             const SchedulerSettings& scheduler_settings);
 
+  void SetupNextBeginFrameIfNeeded();
+  void DrawAndSwapIfPossible();
+  void DrawAndSwapForced();
   void ProcessScheduledActions();
 
   const SchedulerSettings settings_;
   SchedulerClient* client_;
-  scoped_ptr<FrameRateController> frame_rate_controller_;
+
+  base::WeakPtrFactory<Scheduler> weak_factory_;
+  bool last_set_needs_begin_frame_;
+  bool has_pending_begin_frame_;
+  base::TimeTicks last_begin_frame_time_;
+  base::TimeDelta interval_;
+
   SchedulerStateMachine state_machine_;
   bool inside_process_scheduled_actions_;
 
   DISALLOW_COPY_AND_ASSIGN(Scheduler);
 };
 
 }  // namespace cc
 
 #endif  // CC_SCHEDULER_SCHEDULER_H_