const HTMLAttribute* attr = HTMLAttribute::FindHTMLAttribute(aAttrName, &mFirst);
const HTMLAttribute*  attr = HTMLAttribute::FindHTMLAttribute(aAttrName, mFirstUnmapped);
nsHTMLMappedAttributes::HasAttribute(nsIAtom* aAttrName) const{  if (!aAttrName)    return PR_FALSE;  const HTMLAttribute* attr = HTMLAttribute::FindHTMLAttribute(aAttrName, &mFirst);  return attr != nsnull;}