Un-deprecate Element.setAttributeNodeNS()

Source/core/frame/UseCounter.cpp

Index: Source/core/frame/UseCounter.cpp
diff --git a/Source/core/frame/UseCounter.cpp b/Source/core/frame/UseCounter.cpp
index e88891c26bf02b13a1fc00bbc1c31832918ff713..cdb8a1c21a05124dd8e95d406fcc2eedc3b2d788 100644
--- a/Source/core/frame/UseCounter.cpp
+++ b/Source/core/frame/UseCounter.cpp
@@ -754,9 +754,6 @@ String UseCounter::deprecationMessage(Feature feature)
     case PrefixedCancelRequestAnimationFrame:
         return "'webkitCancelRequestAnimationFrame' is vendor-specific. Please use the standard 'cancelAnimationFrame' instead.";
 
-    case ElementSetAttributeNodeNS:
-        return "'Element.setAttributeNodeNS' is deprecated and has been removed from DOM4 (http://w3.org/tr/dom).";
-
     case NodeIteratorDetach:
         return "'NodeIterator.detach' is now a no-op, as per DOM (http://dom.spec.whatwg.org/#dom-nodeiterator-detach).";