Early terminate flings when scrolling impossible

cc/input/input_handler.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_INPUT_INPUT_HANDLER_H_
 #define CC_INPUT_INPUT_HANDLER_H_
 
 #include "base/basictypes.h"
 #include "base/time/time.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/swap_promise_monitor.h"
 #include "cc/input/scrollbar.h"
 
 namespace gfx {
 class Point;
 class PointF;
 class Vector2d;
 class Vector2dF;
 }
 
 namespace ui { struct LatencyInfo; }
 
 namespace cc {
 
 class LayerScrollOffsetDelegate;
 
-struct DidOverscrollParams {
-  gfx::Vector2dF accumulated_overscroll;
-  gfx::Vector2dF latest_overscroll_delta;
-  gfx::Vector2dF current_fling_velocity;
-};
-
 class CC_EXPORT InputHandlerClient {
  public:
   virtual ~InputHandlerClient() {}
 
   virtual void WillShutdown() = 0;
   virtual void Animate(base::TimeTicks time) = 0;
   virtual void MainThreadHasStoppedFlinging() = 0;
 
   // Called when scroll deltas reaching the root scrolling layer go unused.
   // The accumulated overscroll is scoped by the most recent call to
   // InputHandler::ScrollBegin.
-  virtual void DidOverscroll(const DidOverscrollParams& params) = 0;
+  virtual void DidOverscroll(const gfx::Vector2dF& accumulated_overscroll,
+                             const gfx::Vector2dF& latest_overscroll_delta) = 0;
 
  protected:
   InputHandlerClient() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(InputHandlerClient);
 };
 
 // The InputHandler is a way for the embedders to interact with the impl thread
 // side of the compositor implementation. There is one InputHandler per
@@ skipping 32 matching lines @@
   virtual bool ScrollBy(const gfx::Point& viewport_point,
                         const gfx::Vector2dF& scroll_delta) = 0;
 
   virtual bool ScrollVerticallyByPage(const gfx::Point& viewport_point,
                                       ScrollDirection direction) = 0;
 
   // Returns ScrollStarted if a layer was being actively being scrolled,
   // ScrollIgnored if not.
   virtual ScrollStatus FlingScrollBegin() = 0;
 
-  virtual void NotifyCurrentFlingVelocity(const gfx::Vector2dF& velocity) = 0;
-
   virtual void MouseMoveAt(const gfx::Point& mouse_position) = 0;
 
   // Stop scrolling the selected layer. Should only be called if ScrollBegin()
   // returned ScrollStarted.
   virtual void ScrollEnd() = 0;
 
   virtual void SetRootLayerScrollOffsetDelegate(
       LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate) = 0;
 
   // Called when the value returned by
@@ skipping 30 matching lines @@
   InputHandler() {}
   virtual ~InputHandler() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(InputHandler);
 };
 
 }  // namespace cc
 
 #endif  // CC_INPUT_INPUT_HANDLER_H_