Run smooth scroll animations on the compositor when possible

third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h

 /*
  * Copyright (c) 2010, 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 17 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef ScrollAnimatorBase_h
 #define ScrollAnimatorBase_h
 
 #include "platform/PlatformExport.h"
 #include "platform/PlatformWheelEvent.h"
 #include "platform/geometry/FloatSize.h"
 #include "platform/heap/Handle.h"
+#include "platform/scroll/ScrollAnimatorCompositorCoordinator.h"
 #include "platform/scroll/ScrollTypes.h"
 #include "wtf/Forward.h"
 
 namespace blink {
 
 class FloatPoint;
 class ScrollableArea;
 class Scrollbar;
+class WebCompositorAnimationTimeline;
 
-class PLATFORM_EXPORT ScrollAnimatorBase : public NoBaseWillBeGarbageCollectedFinalized<ScrollAnimatorBase> {
+class PLATFORM_EXPORT ScrollAnimatorBase : public ScrollAnimatorCompositorCoordinator {
 public:
     static PassOwnPtrWillBeRawPtr<ScrollAnimatorBase> create(ScrollableArea*);
 
     virtual ~ScrollAnimatorBase();
 
     virtual void dispose() { }
 
     // Computes a scroll destination for the given parameters.  The returned
     // ScrollResultOneDimensional will have didScroll set to false if already at
     // the destination.  Otherwise, starts scrolling towards the destination and
     // didScroll is true.  Scrolling may be immediate or animated. The base
     // class implementation always scrolls immediately, never animates.
     virtual ScrollResultOneDimensional userScroll(ScrollbarOrientation, ScrollGranularity, float step, float delta);
 
     virtual void scrollToOffsetWithoutAnimation(const FloatPoint&);
 
-    ScrollableArea* scrollableArea() const { return m_scrollableArea; }
-
     virtual void setIsActive() { }
 
 #if OS(MACOSX)
     virtual void handleWheelEventPhase(PlatformWheelEventPhase) { }
 #endif
 
     void setCurrentPosition(const FloatPoint&);
     FloatPoint currentPosition() const;
 
     // Returns how much of pixelDelta will be used by the underlying scrollable
     // area.
     virtual float computeDeltaToConsume(ScrollbarOrientation, float pixelDelta) const;
 
-    virtual void cancelAnimations() { }
-    virtual void serviceScrollAnimations() { }
-    virtual bool hasRunningAnimation() const { return false; }
+
+    // ScrollAnimatorCompositorCoordinator implementation.
+    ScrollableArea* scrollableArea() const override { return m_scrollableArea; }
+    void tickAnimation(double monotonicTime) override { };
+    void cancelAnimation() { }

[ajuma, 2015/12/18 19:02:54]

Missing 'override'

[ymalik, 2015/12/18 19:35:47]

Good catch. Thanks!

+    void updateCompositorAnimations() override { };
+    void notifyCompositorAnimationFinished(int groupId) override { };
+    void layerForCompositedScrollingDidChange(WebCompositorAnimationTimeline*) override { };
 
     virtual void contentAreaWillPaint() const { }
     virtual void mouseEnteredContentArea() const { }
     virtual void mouseExitedContentArea() const { }
     virtual void mouseMovedInContentArea() const { }
     virtual void mouseEnteredScrollbar(Scrollbar&) const { }
     virtual void mouseExitedScrollbar(Scrollbar&) const { }
     virtual void willStartLiveResize() { }
     virtual void updateAfterLayout() { }
     virtual void contentsResized() const { }
@@ skipping 24 matching lines @@
     float clampScrollPosition(ScrollbarOrientation, float) const;
 
     RawPtrWillBeMember<ScrollableArea> m_scrollableArea;
     float m_currentPosX; // We avoid using a FloatPoint in order to reduce
     float m_currentPosY; // subclass code complexity.
 };
 
 } // namespace blink
 
 #endif // ScrollAnimatorBase_h