Pre-bind the 'xml' prefix for serialization of XML fragments

Source/core/editing/MarkupAccumulator.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 91 matching lines @@
     , m_resolveURLsMethod(resolveUrlsMethod)
 {
 }
 
 MarkupAccumulator::~MarkupAccumulator()
 {
 }
 
 String MarkupAccumulator::serializeNodes(Node& targetNode, EChildrenOnly childrenOnly, Vector<QualifiedName>* tagNamesToSkip)
 {
-    serializeNodesWithNamespaces(targetNode, childrenOnly, 0, tagNamesToSkip);
+    Namespaces* namespaces = 0;
+    Namespaces namespaceHash;
+    if (!targetNode.document().isHTMLDocument()) {
+        // Add pre-bound namespaces for XML fragments.
+        namespaceHash.set(xmlAtom.impl(), XMLNames::xmlNamespaceURI.impl());
+        namespaces = &namespaceHash;
+    }
+
+    serializeNodesWithNamespaces(targetNode, childrenOnly, namespaces, tagNamesToSkip);
     return m_markup.toString();
 }
 
 void MarkupAccumulator::serializeNodesWithNamespaces(Node& targetNode, EChildrenOnly childrenOnly, const Namespaces* namespaces, Vector<QualifiedName>* tagNamesToSkip)
 {
     if (tagNamesToSkip) {
         for (size_t i = 0; i < tagNamesToSkip->size(); ++i) {
             if (targetNode.hasTagName(tagNamesToSkip->at(i)))
                 return;
         }
@@ skipping 406 matching lines @@
 {
     if (!node.isElementNode() || shouldSelfClose(node) || (!node.hasChildren() && elementCannotHaveEndTag(node)))
         return;
 
     result.appendLiteral("</");
     result.append(nodeNamePreservingCase(toElement(node)));
     result.append('>');
 }
 
 }