nsIContent* aParentContent, nsIAtom* aPseudoTag,
nsIContent* aContent,
PRInt32 StyleSetImpl::RulesMatching(nsISupportsArray* aSheets,                                    nsIPresContext* aPresContext,                                    nsIContent* aParentContent,                                    nsIAtom* aPseudoTag,                                    nsIStyleContext* aParentContext,                                    nsISupportsArray* aResults){  PRInt32 ruleCount = 0;  if (nsnull != aSheets) {    PRInt32 index = aSheets->Count();    while (0 < index--) {      nsIStyleSheet* sheet = (nsIStyleSheet*)aSheets->ElementAt(index);      ruleCount += sheet->RulesMatching(aPresContext, aParentContent, aPseudoTag,                                         aParentContext, aResults);      NS_RELEASE(sheet);    }  }  return ruleCount;}