Limit outstanding surface draw swaps to max_frames_pending.

content/browser/compositor/onscreen_display_client.h

 // Copyright 2014 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 CONTENT_BROWSER_COMPOSITOR_ONSCREEN_DISPLAY_CLIENT_H_
 #define CONTENT_BROWSER_COMPOSITOR_ONSCREEN_DISPLAY_CLIENT_H_
 
 #include "cc/surfaces/display_client.h"
 
 #include "base/memory/ref_counted.h"
@@ skipping 16 matching lines @@
       scoped_ptr<cc::OutputSurface> output_surface,
       cc::SurfaceManager* manager,
       scoped_refptr<base::SingleThreadTaskRunner> task_runner);
   virtual ~OnscreenDisplayClient();
 
   cc::Display* display() { return display_.get(); }
 
   // cc::DisplayClient implementation.
   virtual scoped_ptr<cc::OutputSurface> CreateOutputSurface() OVERRIDE;
   virtual void DisplayDamaged() OVERRIDE;
+  virtual void DidSwapBuffers() OVERRIDE;
+  virtual void DidSwapBuffersComplete() OVERRIDE;
 
  private:
+  void ScheduleDraw();
   void Draw();
 
   scoped_ptr<cc::OutputSurface> output_surface_;
   scoped_ptr<cc::Display> display_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   bool scheduled_draw_;
+  // True if a draw should be scheduled, but it's hit the limit on max frames
+  // pending.
+  bool deferred_draw_;
+  int pending_frames_;
 
   base::WeakPtrFactory<OnscreenDisplayClient> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OnscreenDisplayClient);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_ONSCREEN_DISPLAY_CLIENT_H_