Optimize hasTagName when called on an HTMLElement / SVGElement

Source/core/html/LabelableElement.h

Index: Source/core/html/LabelableElement.h
diff --git a/Source/core/html/LabelableElement.h b/Source/core/html/LabelableElement.h
index 0611008bd7cde5762b27f5b31b63fa2a219ca755..2819a31dcde60991c2a75f57af22d210babee97c 100644
--- a/Source/core/html/LabelableElement.h
+++ b/Source/core/html/LabelableElement.h
@@ -54,11 +54,6 @@ 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();