OverscrollGlow for mainThread-{BLINK CHANGES}

Source/platform/scroll/ScrollableArea.cpp

 /*
  * Copyright (c) 2010, Google Inc. All rights reserved.
  * Copyright (C) 2008, 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 104 matching lines @@
         m_scrollOrigin = origin;
         m_scrollOriginChanged = true;
     }
 }
 
 GraphicsLayer* ScrollableArea::layerForContainer() const
 {
     return layerForScrolling() ? layerForScrolling()->parent() : 0;
 }
 
-bool ScrollableArea::userScroll(ScrollDirectionPhysical direction, ScrollGranularity granularity, float delta)
+ScrollResultOneDimensional ScrollableArea::userScroll(ScrollDirectionPhysical direction, ScrollGranularity granularity, float delta)
 {
     ScrollbarOrientation orientation;
     if (direction == ScrollUp || direction == ScrollDown)
         orientation = VerticalScrollbar;
     else
         orientation = HorizontalScrollbar;
 
     if (!userInputScrollable(orientation))
-        return false;
+        return ScrollResultOneDimensional(false, delta);
 
     cancelProgrammaticScrollAnimation();
 
     float step = 0;
     switch (granularity) {
     case ScrollByLine:
         step = lineStep(orientation);
         break;
     case ScrollByPage:
         step = pageStep(orientation);
         break;
     case ScrollByDocument:
         step = documentStep(orientation);
         break;
     case ScrollByPixel:
     case ScrollByPrecisePixel:
         step = pixelStep(orientation);
         break;
     }
 
     if (direction == ScrollUp || direction == ScrollLeft)
         delta = -delta;
 
-    return scrollAnimator()->userScroll(orientation, granularity, step, delta).didScroll;
+    return scrollAnimator()->userScroll(orientation, granularity, step, delta);
 }
 
 void ScrollableArea::setScrollPosition(const DoublePoint& position, ScrollBehavior behavior)
 {
     // FIXME(417782): This should be unified with LayerScrollableArea::scrollToOffset.
     ASSERT_NOT_REACHED();
 }
 
 void ScrollableArea::scrollToOffsetWithoutAnimation(const FloatPoint& offset, bool cancelProgrammaticAnimations)
 {
@@ skipping 99 matching lines @@
     else
         return false;
 
     return true;
 }
 
 ScrollResult ScrollableArea::handleWheel(const PlatformWheelEvent& wheelEvent)
 {
     // Wheel events which do not scroll are used to trigger zooming.
     if (!wheelEvent.canScroll())
-        return ScrollResult(false);
+        return ScrollResult();
 
     cancelProgrammaticScrollAnimation();
     return scrollAnimator()->handleWheelEvent(wheelEvent);
 }
 
 IntPoint ScrollableArea::adjustScrollPositionWithinRange(const IntPoint& scrollPoint) const
 {
     if (!constrainsScrollingToContentEdge())
         return scrollPoint;
 
@@ skipping 306 matching lines @@
         verticalScrollbarWidth = !verticalBar->isOverlayScrollbar() ? verticalBar->width() : 0;
     if (Scrollbar* horizontalBar = horizontalScrollbar())
         horizontalScrollbarHeight = !horizontalBar->isOverlayScrollbar() ? horizontalBar->height() : 0;
 
     return IntSize(std::max(0, size.width() - verticalScrollbarWidth),
         std::max(0, size.height() - horizontalScrollbarHeight));
 
 }
 
 } // namespace blink