code: function () {
          if (this._focusedItem) {
              Event.removeListener(this._focusedItem,'blur');
              this._focusedItem = null;
          }
          var el;
          while ((el = this._focusHighlightedItems.shift())) {  // yes, it is meant as an assignment, really
              Dom.removeClass(el,YAHOO.widget.TreeView.FOCUS_CLASS_NAME );
          }
      }
docs: Removes the focus of previously selected Node
  @method _removeFocus
  @private