if ((! aAttributes) && (eHTMLUnit_Null != aValue.GetUnit())) {
if (! aAttributes) {
NS_IMETHODIMP HTMLStyleSheetImpl::SetAttributeFor(nsIAtom* aAttribute,                                                   const nsHTMLValue& aValue,                                                  PRBool aMappedToStyle,                                                  nsIHTMLContent* aContent,                                                   nsIHTMLAttributes*& aAttributes){  nsresult  result = NS_OK;  if ((! aAttributes) && (eHTMLUnit_Null != aValue.GetUnit())) {    result = NS_NewHTMLAttributes(&aAttributes);  }  if (aAttributes) {    PRInt32 count;    result = aAttributes->SetAttributeFor(aAttribute, aValue, aMappedToStyle,                                          aContent, this, count);    if (0 == count) {      NS_RELEASE(aAttributes);    }  }  return result;}