Implement closed shadow adjustment for Element.offsetParent

third_party/WebKit/Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 4418 matching lines @@
 {
     if (!m_overflow)
         return borderBoxRect();
     if (hasOverflowClip())
         return m_overflow->selfVisualOverflowRect();
     return unionRect(m_overflow->selfVisualOverflowRect(), m_overflow->contentsVisualOverflowRect());
 }
 
 LayoutUnit LayoutBox::offsetLeft() const
 {
-    return adjustedPositionRelativeToOffsetParent(topLeftLocation()).x();
+    return adjustedPositionRelativeToUnclosedOffsetParent(topLeftLocation()).x();
 }
 
 LayoutUnit LayoutBox::offsetTop() const
 {
-    return adjustedPositionRelativeToOffsetParent(topLeftLocation()).y();
+    return adjustedPositionRelativeToUnclosedOffsetParent(topLeftLocation()).y();
 }
 
 LayoutPoint LayoutBox::flipForWritingModeForChild(const LayoutBox* child, const LayoutPoint& point) const
 {
     if (!style()->isFlippedBlocksWritingMode())
         return point;
 
     // The child is going to add in its x(), so we have to make sure it ends up in
     // the right place.
     return LayoutPoint(point.x() + size().width() - child->size().width() - (2 * child->location().x()), point.y());
@@ skipping 420 matching lines @@
         m_rareData->m_snapAreas->remove(&snapArea);
     }
 }
 
 SnapAreaSet* LayoutBox::snapAreas() const
 {
     return m_rareData ? m_rareData->m_snapAreas.get() : nullptr;
 }
 
 } // namespace blink