   */
    _usesCheckedInsteadOfValue: function(el) {
      if (el.type == 'checkbox' ||
          el.type == 'radio' ||
          el.getAttribute('role') == 'checkbox' ||
          el.getAttribute('role') == 'radio' ||
          el['_hasIronCheckedElementBehavior']) {
        return true;
      }
      return false;
    },

    _useValue: function(el) {
      // Skip disabled elements or elements that don't have a `name` attribute.
      if (el.disabled || !el.name) {
        return false;
      }

      //