Optimize hasTagName when called on an HTMLElement / SVGElement

Source/core/html/LabelableElement.h

 /*
  * Copyright (C) 2012 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 36 matching lines @@
 
     virtual void trace(Visitor*) OVERRIDE;
 
 protected:
     LabelableElement(const QualifiedName& tagName, Document&);
 
 private:
     virtual bool isLabelable() const OVERRIDE FINAL { return true; }
 };
 
-inline bool isLabelableElement(const Element& element)
-{
-    return element.isHTMLElement() && toHTMLElement(element).isLabelable();
-}
-
 inline bool isLabelableElement(const HTMLElement& element)
 {
     return element.isLabelable();
 }
 
 DEFINE_HTMLELEMENT_TYPE_CASTS_WITH_FUNCTION(LabelableElement);
 
 } // namespace blink
 
 #endif