code: function (elm, cls, state) {
          this.$$(elm).toggleClass(cls, state).each(function () {
            if (this.className === '') {
              DomQuery(this).attr('class', null);
            }
          });
        }
docs: Toggles the specified class on/off.
  
  @method toggleClass
  @param {Element} elm Element to toggle class on.
  @param {[type]} cls Class to toggle on/off.
  @param {[type]} state Optional state to set.