Update <use> trees when the referenced element is changed.

Source/core/svg/SVGElementInstance.cpp

 /*
  * Copyright (C) 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  * Copyright (C) 2011 Torch Mobile (Beijing) Co. Ltd. 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 153 matching lines @@
     m_shadowTreeElement = element;
 }
 
 void SVGElementInstance::appendChild(PassRefPtr<SVGElementInstance> child)
 {
     appendChildToContainer<SVGElementInstance, SVGElementInstance>(*child, *this);
 }
 
 void SVGElementInstance::invalidateAllInstancesOfElement(SVGElement* element)
 {
-    if (!element || !element->inDocument())
+    if (!element)
         return;
 
     if (element->instanceUpdatesBlocked())
         return;
 
     const HashSet<SVGElementInstance*>& set = element->instancesForElement();
     if (set.isEmpty())
         return;
 
     // Mark all use elements referencing 'element' for rebuilding
     const HashSet<SVGElementInstance*>::const_iterator end = set.end();
     for (HashSet<SVGElementInstance*>::const_iterator it = set.begin(); it != end; ++it) {
         ASSERT((*it)->shadowTreeElement());
         ASSERT((*it)->shadowTreeElement()->correspondingElement());
         ASSERT((*it)->shadowTreeElement()->correspondingElement() == (*it)->correspondingElement());
         ASSERT((*it)->correspondingElement() == element);
         (*it)->shadowTreeElement()->setCorrespondingElement(0);
 
         if (SVGUseElement* element = (*it)->correspondingUseElement()) {
             ASSERT(element->inDocument());
             element->invalidateShadowTree();
         }
     }
-
-    element->document().updateRenderTreeIfNeeded();
 }
 
 const AtomicString& SVGElementInstance::interfaceName() const
 {
     return EventTargetNames::SVGElementInstance;
 }
 
 ExecutionContext* SVGElementInstance::executionContext() const
 {
     return &m_element->document();
@@ skipping 54 matching lines @@
         m_targetElement->setInstanceUpdatesBlocked(true);
 }
 
 SVGElementInstance::InstanceUpdateBlocker::~InstanceUpdateBlocker()
 {
     if (m_targetElement)
         m_targetElement->setInstanceUpdatesBlocked(false);
 }
 
 }