child = child->mNext;
child = ((CSSStyleSheetImpl*)child)->mNext;
PRBool CSSStyleSheetImpl::ContainsStyleSheet(nsIURL* aURL){  NS_PRECONDITION(nsnull != aURL, "null arg");  PRBool result = (*mURL == *aURL);  CSSStyleSheetImpl*  child = mFirstChild;  while ((PR_FALSE == result) && (nsnull != child)) {    result = child->ContainsStyleSheet(aURL);    child = child->mNext;  }  return result;}