*aValue = nsnull; return NS_CONTENT_ATTR_NOT_THERE;
return result;
nsHTMLMappedAttributes::GetAttribute(nsIAtom* aAttrName,                                     const nsHTMLValue** aValue) const{  if (! aAttrName) {    return NS_ERROR_NULL_POINTER;  }  const HTMLAttribute* attr = HTMLAttribute::FindHTMLAttribute(aAttrName, &mFirst);  if (attr) {    *aValue = &attr->mValue;    return ((attr->mValue.GetUnit() == eHTMLUnit_Null) ?            NS_CONTENT_ATTR_NO_VALUE :            NS_CONTENT_ATTR_HAS_VALUE);  }  *aValue = nsnull;  return NS_CONTENT_ATTR_NOT_THERE;}