.event, 'event (1st arg) should not be null');
  assert_false(!error.source, 'source (2nd arg) should not be null');
  // The spec doesn't define valid values for lineno/colno.
  assert_false(!error.error, 'error (5th arg) should not be null');
}

function assert_rethrown_error_event(error) {
  assert_not_muted_error_event(error);
  assert_equals(error.error.name, rethrowErrorName);
  assert_equals(error.error.message, rethrowErrorMessage);
}

const constructor_throws =
    document.getElementById('construc