code: function _moveWorkingSetItem(paneId, fromIndex, toIndex) {
          var pane = _getPane(paneId);
  
          pane.moveWorkingSetItem(fromIndex, toIndex);
          exports.trigger("workingSetSort", pane.id);
          exports.trigger("_workingSetDisableAutoSort", pane.id);
      }
docs: moves a working set item from one index to another shifting the items
  after in the working set up and reinserting it at the desired location
  @param {!string} paneId - id of the pane to sort
  @param {!number} fromIndex - the index of the item to move
  @param {!number} toIndex - the index to move to
  @private