ion() {
        // Initialized to the window location's path.
        expect(window.location.pathname).to.be.equal(urlElem.path);

        // Changing the urlElem's path changes the URL
        urlElem.path = '/foo/bar';
        expect(window.location.pathname).to.be.equal('/foo/bar');

        // Changing the path and sending a custom event on the window changes
        // the urlElem.
        replaceState('/baz');
        window.dispatchEvent(new CustomEvent('location-changed'));
        expect(urlElem.pa