Drop const_iterator for AttributeCollection

Source/core/dom/ElementData.cpp

Index: Source/core/dom/ElementData.cpp
diff --git a/Source/core/dom/ElementData.cpp b/Source/core/dom/ElementData.cpp
index 621edda59ce5d87db4c1955c8477f21ec16d274c..c7c8e6cc052d95f3524ad6369da62f81d69e9623 100644
--- a/Source/core/dom/ElementData.cpp
+++ b/Source/core/dom/ElementData.cpp
@@ -114,8 +114,8 @@ bool ElementData::isEquivalent(const ElementData* other) const
     if (attributes.size() != otherAttributes.size())
         return false;
 
-    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) {
         const Attribute* otherAttr = otherAttributes.find(it->name());
         if (!otherAttr || it->value() != otherAttr->value())
             return false;