Maintain child dependent ComputedStyle flags if propagation stops.

Source/core/style/ComputedStyle.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2011 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 1724 matching lines @@
         borderBottomIsTransparent(),
         horizontal || includeLogicalRightEdge);
 
     edges[BSLeft] = BorderEdge(borderLeftWidth(),
         visitedDependentColor(CSSPropertyBorderLeftColor),
         borderLeftStyle(),
         borderLeftIsTransparent(),
         !horizontal || includeLogicalLeftEdge);
 }
 
+void ComputedStyle::copyChildDependentFlagsFrom(const ComputedStyle& other)
+{
+    setEmptyState(other.emptyState());
+    if (other.hasExplicitlyInheritedProperties())
+        setHasExplicitlyInheritedProperties();
+}
+
 } // namespace blink