mSheet = aSheet; NS_ADDREF(aSheet);
mSheet = nsnull;
CSSParserImpl::CSSParserImpl(nsICSSStyleSheet* aSheet){  NS_INIT_REFCNT();  nsCSSAtoms::AddrefAtoms();  mScanner = nsnull;  mSheet = aSheet; NS_ADDREF(aSheet);  mHavePushBack = PR_FALSE;  mNavQuirkMode = PR_TRUE;  mCaseSensitive = PR_FALSE;}