code: function(child, toIndex, lastIndex) {
        // If the index of `child` is less than `lastIndex`, then it needs to
        // be moved. Otherwise, we do not need to move it because a child will be
        // inserted or moved before `child`.
        if (child._mountIndex < lastIndex) {
          enqueueMove(this._rootNodeID, child._mountIndex, toIndex);
        }
      }
docs: Moves a child component to the supplied index.
  
  @param {ReactComponent} child Component to move.
  @param {number} toIndex Destination index of the element.
  @param {number} lastIndex Last index visited of the siblings of `child`.
  @protected