OverscrollGlow for mainThread-{BLINK CHANGES}

Source/core/frame/LocalFrame.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Simon Hausmann <hausmann@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  *                     2001 George Staikos <staikos@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov <ap@nypop.com>
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
@@ skipping 696 matching lines @@
 bool LocalFrame::shouldReuseDefaultView(const KURL& url) const
 {
     return loader().stateMachine()->isDisplayingInitialEmptyDocument() && document()->isSecureTransitionTo(url);
 }
 
 void LocalFrame::removeSpellingMarkersUnderWords(const Vector<String>& words)
 {
     spellChecker().removeSpellingMarkersUnderWords(words);
 }
 
-static bool scrollAreaOnBothAxes(const FloatSize& delta, ScrollableArea& view)
+static ScrollResult scrollAreaOnBothAxes(const FloatSize& delta, ScrollableArea& view)
 {
-    bool scrolledHorizontal = view.scroll(ScrollLeft, ScrollByPrecisePixel, delta.width());
-    bool scrolledVertical = view.scroll(ScrollUp, ScrollByPrecisePixel, delta.height());
-    return scrolledHorizontal || scrolledVertical;
+    ScrollResultOneDimensional horizontal = view.scroll(ScrollLeft, ScrollByPrecisePixel, delta.width());
+    ScrollResultOneDimensional vertical = view.scroll(ScrollUp, ScrollByPrecisePixel, delta.height());
+    return ScrollResult((horizontal.didScroll || vertical.didScroll), horizontal.unusedScrollDelta, vertical.unusedScrollDelta);
 }
 
-// Returns true if a scroll occurred.
-bool LocalFrame::applyScrollDelta(const FloatSize& delta, bool isScrollBegin)
+ScrollResult LocalFrame::applyScrollDelta(const FloatSize& delta, bool isScrollBegin)
 {
     if (isScrollBegin)
         host()->topControls().scrollBegin();
 
     if (!view() || delta.isZero())
-        return false;
+        return ScrollResult(false, delta.width(), delta.height());
 
     FloatSize remainingDelta = delta;
 
     // If this is main frame, allow top controls to scroll first.
     if (shouldScrollTopControls(delta))
         remainingDelta = host()->topControls().scrollBy(remainingDelta);
 
     if (remainingDelta.isZero())
-        return true;
+        return ScrollResult(true);
 
-    bool consumed = remainingDelta != delta;
+    ScrollResult result = scrollAreaOnBothAxes(remainingDelta, *view()->scrollableArea());
 
-    if (scrollAreaOnBothAxes(remainingDelta, *view()->scrollableArea()))
-        return true;
+    if (result.didScroll)
+        return result;
 
-    return consumed;
+    result.didScroll = remainingDelta != delta;
+    return result;
 }
 
 bool LocalFrame::shouldScrollTopControls(const FloatSize& delta) const
 {
     if (!isMainFrame())
         return false;
 
     // Always give the delta to the top controls if the scroll is in
     // the direction to show the top controls. If it's in the
     // direction to hide the top controls, only give the delta to the
@@ skipping 55 matching lines @@
     , m_textZoomFactor(parentTextZoomFactor(this))
     , m_inViewSourceMode(false)
 {
     if (isLocalRoot())
         m_instrumentingAgents = InstrumentingAgents::create();
     else
         m_instrumentingAgents = localFrameRoot()->m_instrumentingAgents;
 }
 
 } // namespace blink