static fromPlainObject(response) {
    if (response && typeof response['tenantId'] !== 'undefined') {
      return new firebaseui.auth.RedirectStatus(response['tenantId']);
    }
    return null;
  }
@param {?Object} response The plain object presentation of a potential
    redirect status object.
@return {?firebaseui.auth.RedirectStatus} The redirect status
    representation of the provided object.