cc: Save correct frame begin time to FrameRateCounter

cc/frame_rate_controller.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_FRAME_RATE_CONTROLLER_H_
 #define CC_FRAME_RATE_CONTROLLER_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 39 matching lines @@
     // If the rendering pipeline crashes, call didAbortAllPendingFrames.
     void didBeginFrame();
     void didFinishFrame();
     void didAbortAllPendingFrames();
     void setMaxFramesPending(int); // 0 for unlimited.
     int maxFramesPending() const { return m_maxFramesPending; }
 
     // This returns null for unthrottled frame-rate.
     base::TimeTicks nextTickTime();
 
+    // This returns now for unthrottled frame-rate.
+    base::TimeTicks lastTickTime();
+
     void setTimebaseAndInterval(base::TimeTicks timebase, base::TimeDelta interval);
     void setSwapBuffersCompleteSupported(bool);
 
 protected:
     friend class FrameRateControllerTimeSourceAdapter;
     void onTimerTick();
 
     void postManualTick();
     void manualTick();
 
     FrameRateControllerClient* m_client;
     int m_numFramesPending;
     int m_maxFramesPending;
     scoped_refptr<TimeSource> m_timeSource;
     scoped_ptr<FrameRateControllerTimeSourceAdapter> m_timeSourceClientAdapter;
     bool m_active;
     bool m_swapBuffersCompleteSupported;
 
     // Members for unthrottled frame-rate.
     bool m_isTimeSourceThrottling;
     base::WeakPtrFactory<FrameRateController> m_weakFactory;
     Thread* m_thread;
 
     DISALLOW_COPY_AND_ASSIGN(FrameRateController);
 };
 
 }  // namespace cc
 
 #endif  // CC_FRAME_RATE_CONTROLLER_H_