le = function() {
      this.setAttribute('tabIndex', -1);
    }
  </script>

  <template id="x-test"><div>before</div><slot></slot><div>after</div></template>
  <script>
    defineTestElement('x-test');
  </script>

<script>

  'use strict';

  suite('nativeTree', function() {

    let el;

    setup(function() {
      el = document.createElement('x-test');
      let d = document.createElement('div');
      d.textContent = 'content';
      el.appendChild(d);
      document.body.appendChild(el);
      Shady