Use float for scroll offset.

third_party/WebKit/Source/platform/mac/ScrollAnimatorMac.h

 /*
  * Copyright (C) 2010, 2011 Apple 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 38 matching lines @@
 
 class PLATFORM_EXPORT ScrollAnimatorMac : public ScrollAnimatorBase {
   USING_PRE_FINALIZER(ScrollAnimatorMac, dispose);
 
  public:
   ScrollAnimatorMac(ScrollableArea*);
   ~ScrollAnimatorMac() override;
 
   void dispose() override;
 
-  void immediateScrollToPointForScrollAnimation(const FloatPoint& newPosition);
+  void immediateScrollToOffsetForScrollAnimation(const ScrollOffset& newOffset);
   bool haveScrolledSincePageLoad() const { return m_haveScrolledSincePageLoad; }
 
   void updateScrollerStyle();
 
   bool scrollbarPaintTimerIsActive() const;
   void startScrollbarPaintTimer();
   void stopScrollbarPaintTimer();
 
-  void sendContentAreaScrolledSoon(const FloatSize& scrollDelta);
+  void sendContentAreaScrolledSoon(const ScrollOffset& scrollDelta);
 
   void setVisibleScrollerThumbRect(const IntRect&);
 
   DEFINE_INLINE_VIRTUAL_TRACE() { ScrollAnimatorBase::trace(visitor); }
 
  private:
   RetainPtr<id> m_scrollAnimationHelper;
   RetainPtr<BlinkScrollAnimationHelperDelegate> m_scrollAnimationHelperDelegate;
 
   RetainPtr<ScrollbarPainterController> m_scrollbarPainterController;
   RetainPtr<BlinkScrollbarPainterControllerDelegate>
       m_scrollbarPainterControllerDelegate;
   RetainPtr<BlinkScrollbarPainterDelegate> m_horizontalScrollbarPainterDelegate;
   RetainPtr<BlinkScrollbarPainterDelegate> m_verticalScrollbarPainterDelegate;
 
   void initialScrollbarPaintTask();
   std::unique_ptr<CancellableTaskFactory> m_initialScrollbarPaintTaskFactory;
 
   void sendContentAreaScrolledTask();
   std::unique_ptr<CancellableTaskFactory> m_sendContentAreaScrolledTaskFactory;
   std::unique_ptr<WebTaskRunner> m_taskRunner;
-  FloatSize m_contentAreaScrolledTimerScrollDelta;
+  ScrollOffset m_contentAreaScrolledTimerScrollDelta;
 
-  ScrollResult userScroll(ScrollGranularity, const FloatSize& delta) override;
-  void scrollToOffsetWithoutAnimation(const FloatPoint&) override;
+  ScrollResult userScroll(ScrollGranularity,
+                          const ScrollOffset& delta) override;
+  void scrollToOffsetWithoutAnimation(const ScrollOffset&) override;
 
   void handleWheelEventPhase(PlatformWheelEventPhase) override;
 
   void cancelAnimation() override;
 
   void contentAreaWillPaint() const override;
   void mouseEnteredContentArea() const override;
   void mouseExitedContentArea() const override;
   void mouseMovedInContentArea() const override;
   void mouseEnteredScrollbar(Scrollbar&) const override;
   void mouseExitedScrollbar(Scrollbar&) const override;
   void contentsResized() const override;
   void contentAreaDidShow() const override;
   void contentAreaDidHide() const override;
   void didBeginScrollGesture() const;
   void didEndScrollGesture() const;
   void mayBeginScrollGesture() const;
 
   void finishCurrentScrollAnimations() override;
 
   void didAddVerticalScrollbar(Scrollbar&) override;
   void willRemoveVerticalScrollbar(Scrollbar&) override;
   void didAddHorizontalScrollbar(Scrollbar&) override;
   void willRemoveHorizontalScrollbar(Scrollbar&) override;
 
   bool shouldScrollbarParticipateInHitTesting(Scrollbar&) override;
 
-  void notifyContentAreaScrolled(const FloatSize& delta) override;
+  void notifyContentAreaScrolled(const ScrollOffset& delta) override;
 
   bool setScrollbarsVisibleForTesting(bool) override;
 
-  FloatPoint adjustScrollPositionIfNecessary(const FloatPoint&) const;
+  ScrollOffset adjustScrollOffsetIfNecessary(const ScrollOffset&) const;
 
-  void immediateScrollTo(const FloatPoint&);
+  void immediateScrollTo(const ScrollOffset&);
 
   bool m_haveScrolledSincePageLoad;
   bool m_needsScrollerStyleUpdate;
   IntRect m_visibleScrollerThumbRect;
 };
 
 }  // namespace blink
 
 #endif  // ScrollAnimatorMac_h