Initialize GC mixin bases only when leftmost vtable has been initialized.

Source/core/svg/SVGPatternElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) Research In Motion Limited 2010. 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 15 matching lines @@
 #include "core/XLinkNames.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/rendering/svg/RenderSVGResourcePattern.h"
 #include "core/svg/PatternAttributes.h"
 #include "platform/transforms/AffineTransform.h"
 
 namespace blink {
 
 inline SVGPatternElement::SVGPatternElement(Document& document)
     : SVGElement(SVGNames::patternTag, document)
-    , SVGURIReference(this)
-    , SVGTests(this)
-    , SVGFitToViewBox(this)
     , m_x(SVGAnimatedLength::create(this, SVGNames::xAttr, SVGLength::create(LengthModeWidth), AllowNegativeLengths))
     , m_y(SVGAnimatedLength::create(this, SVGNames::yAttr, SVGLength::create(LengthModeHeight), AllowNegativeLengths))
     , m_width(SVGAnimatedLength::create(this, SVGNames::widthAttr, SVGLength::create(LengthModeWidth), ForbidNegativeLengths))
     , m_height(SVGAnimatedLength::create(this, SVGNames::heightAttr, SVGLength::create(LengthModeHeight), ForbidNegativeLengths))
     , m_patternTransform(SVGAnimatedTransformList::create(this, SVGNames::patternTransformAttr, SVGTransformList::create()))
     , m_patternUnits(SVGAnimatedEnumeration<SVGUnitTypes::SVGUnitType>::create(this, SVGNames::patternUnitsAttr, SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX))
     , m_patternContentUnits(SVGAnimatedEnumeration<SVGUnitTypes::SVGUnitType>::create(this, SVGNames::patternContentUnitsAttr, SVGUnitTypes::SVG_UNIT_TYPE_USERSPACEONUSE))
 {
+    SVGURIReference::initialize(this);
+    SVGTests::initialize(this);
+    SVGFitToViewBox::initialize(this);
+
     addToPropertyMap(m_x);
     addToPropertyMap(m_y);
     addToPropertyMap(m_width);
     addToPropertyMap(m_height);
     addToPropertyMap(m_patternTransform);
     addToPropertyMap(m_patternUnits);
     addToPropertyMap(m_patternContentUnits);
 }
 
 void SVGPatternElement::trace(Visitor* visitor)
@@ skipping 142 matching lines @@
 
 bool SVGPatternElement::selfHasRelativeLengths() const
 {
     return m_x->currentValue()->isRelative()
         || m_y->currentValue()->isRelative()
         || m_width->currentValue()->isRelative()
         || m_height->currentValue()->isRelative();
 }
 
 } // namespace blink