t navigator.credentials.create(makeCreateOptions([]));
        } catch (e) {
            switch (e.name) {
                case "NotAllowedError":
                    enabled = false;
                    break;
                case "TypeError":
                    enabled = true;
                    break;
                default:
                    throw e;
            }
        } finally {
            window.parent.postMessage({ type, enabled }, "*");
        }
    }
    test_driver.set_test_context(pare