Function timeout

test/fixtures/wpt/resources/testharness.js:4199–4203

* Timeout the tests. * * This only has an effect when ``explicit_timeout`` has been set * in :js:func:`setup`. In other cases any call is a no-op. *

()

     *
     */
    function timeout() {
        if (tests.timeout_length === null) {
            tests.timeout();
        }
    }
    expose(timeout, 'timeout');

    /**