Absolute positioned child with percent should include containing block padding

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 1634 matching lines @@
         height -= cb->paddingLogicalHeight();
     return height;
 }
 
 LayoutUnit LayoutBox::containingBlockLogicalWidthForContent() const
 {
     if (hasOverrideContainingBlockLogicalWidth())
         return overrideContainingBlockContentLogicalWidth();
 
     LayoutBlock* cb = containingBlock();
+    if (isOutOfFlowPositioned())
+        return cb->clientLogicalWidth();
     return cb->availableLogicalWidth();
 }
 
 LayoutUnit LayoutBox::containingBlockLogicalHeightForContent(AvailableLogicalHeightType heightType) const
 {
     if (hasOverrideContainingBlockLogicalHeight())
         return overrideContainingBlockContentLogicalHeight();
 
     LayoutBlock* cb = containingBlock();
     return cb->availableLogicalHeight(heightType);
@@ skipping 3185 matching lines @@
     if (!flowThread) {
         // If there's no flow thread, we're not nested. All pages have the same height. Give up.
         return strutToNextPage;
     }
     // Start searching for a suitable offset at the top of the next page or column.
     LayoutUnit flowThreadOffset = offsetFromLogicalTopOfFirstPage() + nextPageLogicalTop;
     return strutToNextPage + flowThread->nextLogicalTopForUnbreakableContent(flowThreadOffset, contentLogicalHeight) - flowThreadOffset;
 }
 
 } // namespace blink