Consistently use AtomicString for namespaceURI / prefix

Source/core/xml/XPathParser.cpp

 /*
  * Copyright 2005 Maksim Orlovich <maksim@kde.org>
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  *
  * 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
@@ skipping 429 matching lines @@
     case NUMBER:
     case NAMETEST:
         yylval->str = new String(tok.str);
         registerString(yylval->str);
         break;
     }
 
     return tok.type;
 }
 
-bool Parser::expandQName(const String& qName, String& localName, String& namespaceURI)
+bool Parser::expandQName(const String& qName, AtomicString& localName, AtomicString& namespaceURI)
 {
     size_t colon = qName.find(':');
     if (colon != kNotFound) {
         if (!m_resolver)
             return false;
         namespaceURI = m_resolver->lookupNamespaceURI(qName.left(colon));
         if (namespaceURI.isNull())
             return false;
-        localName = qName.substring(colon + 1);
-    } else
-        localName = qName;
+        localName = AtomicString(qName.substring(colon + 1));
+    } else {
+        localName = AtomicString(qName);
+    }
 
     return true;
 }
 
 Expression* Parser::parseStatement(const String& statement, PassRefPtr<XPathNSResolver> resolver, ExceptionState& exceptionState)
 {
     reset(statement);
 
     m_resolver = resolver;
 
@@ skipping 143 matching lines @@
 {
     if (t == 0)
         return;
 
     ASSERT(m_nodeTests.contains(t));
 
     m_nodeTests.remove(t);
     delete t;
 }