code: function (val) {
              var carousel = this,
                  cssClass = carousel.CLASSES;
  
              if (val) {
                  carousel.replaceClass(cssClass.HORIZONTAL, cssClass.VERTICAL);
              } else {
                  carousel.replaceClass(cssClass.VERTICAL, cssClass.HORIZONTAL);
              }
              this._itemAttrCache = {}; // force recomputed next time
  
              return val;
          }
docs: Set the orientation of the Carousel.
  
  @method _setOrientation
  @param val {Boolean} The new value for isVertical
  @return {Boolean} The new value that would be set
  @protected