    assert_true(cert instanceof RTCCertificate,
        'Expect cert to be instance of RTCCertificate');

      assert_greater_than(cert.expires, Date.now(),
        'Expect generated certificate to expire reasonably long after current time');
    }),
    'generateCertificate() with compulsary ECDSA parameters should succeed');

  /*
   *  4.10. A user agent must reject a call to generateCertificate() with a
   *        DOMException of type NotSupportedError if the keygenAlgorithm
   *        parameter iden