Move instead of clone shadow tree children

Source/core/svg/SVGUseElement.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 2009-2010. All rights reserved.
  * Copyright (C) 2011 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  * Copyright (C) 2012 University of Szeged
  * Copyright (C) 2012 Renata Hodovan <reni@webkit.org>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 632 matching lines @@
 
         ASSERT(referencedScope());
         Element* targetElement = SVGURIReference::targetElementFromIRIString(use->hrefString(), *referencedScope());
         SVGElement* target = 0;
         if (targetElement && targetElement->isSVGElement())
             target = toSVGElement(targetElement);
 
         // Don't ASSERT(target) here, it may be "pending", too.
         // Setup sub-shadow tree root node
         RefPtr<SVGGElement> cloneParent = SVGGElement::create(referencedScope()->document());
-        use->cloneChildNodes(cloneParent.get());
+        for (Node* child = use->firstChild(); child;) {
+            Node* oldChild = child;
+            child = child->nextSibling();
+            cloneParent->appendChild(oldChild);
+        }
 
         // Spec: In the generated content, the 'use' will be replaced by 'g', where all attributes from the
         // 'use' element except for x, y, width, height and xlink:href are transferred to the generated 'g' element.
         transferUseAttributesToReplacedElement(use, cloneParent.get());
 
         if (target && !isDisallowedElement(target)) {
             RefPtr<Element> newChild = target->cloneElementWithChildren();
             ASSERT(newChild->isSVGElement());
             transferUseWidthAndHeightIfNeeded(*use, toSVGElement(newChild.get()), *target);
             cloneParent->appendChild(newChild.release());
@@ skipping 34 matching lines @@
         // height are provided on the 'use' element, then these attributes will be transferred to
         // the generated 'svg'. If attributes width and/or height are not specified, the generated
         // 'svg' element will use values of 100% for these attributes.
         ASSERT(referencedScope());
         RefPtr<SVGSVGElement> svgElement = SVGSVGElement::create(referencedScope()->document());
 
         // Transfer all data (attributes, etc.) from <symbol> to the new <svg> element.
         svgElement->cloneDataFromElement(*toElement(element));
 
         // Only clone symbol children, and add them to the new <svg> element
-        for (Node* child = element->firstChild(); child; child = child->nextSibling()) {
-            RefPtr<Node> newChild = child->cloneNode(true);
-            svgElement->appendChild(newChild.release());
+        for (Node* child = toSVGElement(element)->firstChild(); child;) {
+            Node* oldChild = child;
+            child = child->nextSibling();
+            svgElement->appendChild(oldChild);
         }
 
         // We don't walk the target tree element-by-element, and clone each element,
         // but instead use cloneNode(deep=true). This is an optimization for the common
         // case where <use> doesn't contain disallowed elements (ie. <foreignObject>).
         // Though if there are disallowed elements in the subtree, we have to remove them.
         // For instance: <use> on <g> containing <foreignObject> (indirect case).
         if (subtreeContainsDisallowedElement(svgElement.get()))
             removeDisallowedElementsFromSubtree(*svgElement);
 
@@ skipping 199 matching lines @@
 
     if (m_resource)
         m_resource->removeClient(this);
 
     m_resource = resource;
     if (m_resource)
         m_resource->addClient(this);
 }
 
 }