code: function traverseToNextViewByMRU(direction) {
          var file = getCurrentlyViewedFile(),
              paneId = getActivePaneId(),
              index = _.findIndex(_mruList, function (record) {
                  return (record.file === file && record.paneId === paneId);
              });
  
          return ViewUtils.traverseViewArray(_mruList, index, direction);
      }
docs: Get the next or previous file in the MRU list.
  @param {!number} direction - Must be 1 or -1 to traverse forward or backward
  @return {?{file:File, paneId:string}} The File object of the next item in the traversal order or null if there aren't any files to traverse.
  May return current file if there are no other files to traverse.