code: function _makeMROFListEntry(path, pane, cursorPos) {
          return {
              file: path,
              paneId: pane,
              cursor: cursorPos
          };
      }
docs: Creates an entry for MROF list
  @private
  @param {String} path - full path of a doc
  @param {String} pane - the pane holding the editor for the doc
  @param {Object} cursorPos - current cursor position
  @return {Object} a frame containing file path, pane and last known cursor