const char* spec,
const nsAReadableString& spec,
NS_NewURI(nsIURI* *result,           const char* spec,           nsIURI* baseURI = nsnull,          nsIIOService* ioService = nsnull)     // pass in nsIIOService to optimize callers{    nsresult rv;    nsCOMPtr<nsIIOService> serv;    if (ioService == nsnull) {        serv = do_GetIOService(&rv);        if (NS_FAILED(rv)) return rv;        ioService = serv.get();    }    return ioService->NewURI(spec, baseURI, result);}