return doc->SetDocumentCharacterSet(aCharset);
doc->SetDocumentCharacterSet(aCharset);
XULContentSinkImpl::SetDocumentCharset(nsACString& aCharset){    nsCOMPtr<nsIDocument> doc = do_QueryReferent(mDocument);    if (doc) {        return doc->SetDocumentCharacterSet(aCharset);    }      return NS_OK;}