Blink Support for Overlay Scrollbar Animation

Source/platform/scroll/Scrollbar.h

 /*
  * Copyright (C) 2004, 2006 Apple Computer, 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
@@ skipping 12 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef Scrollbar_h
 #define Scrollbar_h
 
 #include "platform/Timer.h"
 #include "platform/Widget.h"
 #include "platform/scroll/ScrollTypes.h"
 #include "platform/scroll/ScrollbarThemeClient.h"
+#include "public/platform/WebThemeEngine.h"
 #include "wtf/MathExtras.h"
 #include "wtf/PassRefPtr.h"
 
 namespace blink {
 
 class GraphicsContext;
 class IntRect;
 class PlatformGestureEvent;
 class PlatformMouseEvent;
 class ScrollableArea;
@@ skipping 51 matching lines @@
     virtual ScrollbarPart hoveredPart() const OVERRIDE { return m_hoveredPart; }
 
     virtual void styleChanged() OVERRIDE { }
 
     virtual bool enabled() const OVERRIDE { return m_enabled; }
     virtual void setEnabled(bool) OVERRIDE;
 
     // Called by the ScrollableArea when the scroll offset changes.
     void offsetDidChange();
 
+    void updateStateTransitionData(blink::WebThemeEngine::State, blink::WebThemeEngine::State, double);
+
     void disconnectFromScrollableArea() { m_scrollableArea = 0; }
     ScrollableArea* scrollableArea() const { return m_scrollableArea; }
 
     int pressedPos() const { return m_pressedPos; }
 
     virtual void setHoveredPart(ScrollbarPart);
     virtual void setPressedPart(ScrollbarPart);
 
     void setProportion(int visibleSize, int totalSize);
     void setPressedPos(int p) { m_pressedPos = p; }
 
     virtual void paint(GraphicsContext*, const IntRect& damageRect) OVERRIDE;
 
     virtual bool isOverlayScrollbar() const OVERRIDE;
     bool shouldParticipateInHitTesting();
 
+    virtual bool isDuringStateTransitionAnimation() const OVERRIDE;
+    virtual double stateTransitionProgress() const OVERRIDE;
+    virtual blink::WebThemeEngine::State stateTransitionStartState() const OVERRIDE;
+    virtual blink::WebThemeEngine::State stateTransitionEndState() const OVERRIDE;
+
     bool isWindowActive() const;
 
     bool gestureEvent(const PlatformGestureEvent&);
 
     // These methods are used for platform scrollbars to give :hover feedback.  They will not get called
     // when the mouse went down in a scrollbar, since it is assumed the scrollbar will start
     // grabbing all events in that case anyway.
     void mouseMoved(const PlatformMouseEvent&);
     void mouseEntered();
     void mouseExited();
@@ skipping 53 matching lines @@
 
     bool m_enabled;
 
     Timer<Scrollbar> m_scrollTimer;
     bool m_overlapsResizer;
 
     bool m_suppressInvalidation;
 
     bool m_isAlphaLocked;
 
+    double m_stateTransitionProgress;
+    blink::WebThemeEngine::State m_startState;
+    blink::WebThemeEngine::State m_endState;
+
 private:
     virtual bool isScrollbar() const OVERRIDE { return true; }
 
     float scrollableAreaCurrentPos() const;
 };
 
 DEFINE_TYPE_CASTS(Scrollbar, Widget, widget, widget->isScrollbar(), widget.isScrollbar());
 
 } // namespace blink
 
 #endif // Scrollbar_h