 <div id="foo"></div>
      <div class="thing"></div>
      <x-inner-dir></x-inner-dir>
    </template>
    <script type="module">
import '../../polymer-legacy.js';
import { DirMixin } from '../../lib/mixins/dir-mixin.js';
import { PolymerElement } from '../../polymer-element.js';
class XDir extends DirMixin(PolymerElement) {
  static get is() {return 'x-dir';}
}
customElements.define(XDir.is, XDir);
</script>
  </dom-module>

  <dom-module id="x-dir-legacy">
    <template>
      <style>
        :host {
   