Clamp shape-margin to zero

Source/core/css/StylePropertySet.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. 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 339 matching lines @@
 void MutableStylePropertySet::addParsedProperties(const WillBeHeapVector<CSSProperty, 256>& properties)
 {
     m_propertyVector.reserveCapacity(m_propertyVector.size() + properties.size());
     for (unsigned i = 0; i < properties.size(); ++i)
         addParsedProperty(properties[i]);
 }
 
 void MutableStylePropertySet::addParsedProperty(const CSSProperty& property)
 {
     // Only add properties that have no !important counterpart present
-    if (!propertyIsImportant(property.id()) || property.isImportant())
+    if (!propertyIsImportant(property.id()) || property.isImportant() || forceOverride())
         setProperty(property);
 }
 
 String StylePropertySet::asText() const
 {
     return StylePropertySerializer(*this).asText();
 }
 
 void MutableStylePropertySet::mergeAndOverrideOnConflict(const StylePropertySet* other)
 {
@@ skipping 236 matching lines @@
     result.appendLiteral(": ");
     result.append(propertyValue()->cssText());
     if (isImportant())
         result.appendLiteral(" !important");
     result.append(';');
     return result.toString();
 }
 
 
 } // namespace blink