text: import 'babel-polyfill';
  import 'custom-event-polyfill';
  import 'whatwg-fetch';
  import 'document-register-element';
  
  // hack: https://phabricator.babeljs.io/T1548
  if (typeof HTMLElement !== 'function') {
    var _HTMLElement = function () {};
    _HTMLElement.prototype = HTMLElement.prototype;
    HTMLElement = _HTMLElement; // eslint-disable-line no-native-reassign
  }
  