Forward velocity to the fling gesture handler.

Source/Platform/chromium/public/WebInputHandlerClient.h

 /* Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
@@ skipping 50 matching lines @@
 
     // Scroll the selected layer vertically by one logical page in the given
     // direction.
     virtual bool scrollVerticallyByPageIfPossible(WebPoint origin, WebScrollbar::ScrollDirection) = 0;
 
     // Push velocity updates for the duration of animated fling gestures.
     virtual void notifyCurrentFlingVelocity(WebFloatSize velocity) { }
 
     // Returns ScrollStarted if a layer was being actively being scrolled,
     // ScrollIgnored if not.
-    virtual ScrollStatus flingScrollBegin() = 0;
+    virtual ScrollStatus flingScrollBegin(WebFloatSize velocity) = 0;
 
     // Stop scrolling the selected layer. Should only be called if scrollBegin()
     // returned ScrollStarted.
     virtual void scrollEnd() = 0;
 
     virtual void pinchGestureBegin() = 0;
     virtual void pinchGestureUpdate(float magnifyDelta, WebPoint anchor) = 0;
     virtual void pinchGestureEnd() = 0;
 
     virtual void startPageScaleAnimation(WebSize targetPosition,
@@ skipping 14 matching lines @@
     // monotonicallyIncreasingTime().
     virtual void didReceiveLastInputEventForVSync(double frameTimeSeconds) { }
 
 protected:
     virtual ~WebInputHandlerClient() { }
 };
 
 }
 
 #endif