Drop const_iterator for AttributeCollection

Source/core/xml/XPathNodeSet.cpp

Index: Source/core/xml/XPathNodeSet.cpp
diff --git a/Source/core/xml/XPathNodeSet.cpp b/Source/core/xml/XPathNodeSet.cpp
index 33b619180fb10ab9e869343e7a539ece706e4b25..f02d8904674a68e6bb21c13f562fb4f083a7938e 100644
--- a/Source/core/xml/XPathNodeSet.cpp
+++ b/Source/core/xml/XPathNodeSet.cpp
@@ -235,8 +235,8 @@ void NodeSet::traversalSort() const
 
         Element* element = toElement(n);
         AttributeCollection attributes = element->attributes();
-        AttributeCollection::const_iterator end = attributes.end();
-        for (AttributeCollection::const_iterator it = attributes.begin(); it != end; ++it) {
+        AttributeCollection::iterator end = attributes.end();
+        for (AttributeCollection::iterator it = attributes.begin(); it != end; ++it) {
             RefPtrWillBeRawPtr<Attr> attr = element->attrIfExists(it->name());
             if (attr && nodes.contains(attr.get()))
                 sortedNodes.append(attr);