MOZ_COUNT_DTOR(HTMLCSSStyleSheetImpl);
HTMLCSSStyleSheetImpl::~HTMLCSSStyleSheetImpl(){  MOZ_COUNT_DTOR(HTMLCSSStyleSheetImpl);  NS_RELEASE(mURL);  if (nsnull != mFirstLineRule) {    mFirstLineRule->mSheet = nsnull;    NS_RELEASE(mFirstLineRule);  }  if (nsnull != mFirstLetterRule) {    mFirstLetterRule->mSheet = nsnull;    NS_RELEASE(mFirstLetterRule);  }}