static get attributes() {
    return [
      attributes.EXPANDED,
      attributes.ROOT_ITEM,
      attributes.SELECTED
    ];
  }
/**
   * Return the attributes we handle as getters/setters
   * @returns {Array} The attributes in an array
   */
Return the attributes we handle as getters/setters
@returns {Array} The attributes in an array
Return the attributes we handle as getters / setters @returns { Array } The attributes in an array
static get attributes() {
    return [
      attributes.EXPANDED,
      attributes.ROOT_ITEM,
      attributes.SELECTED
    ];
  }
static get attributes ( ) { return [ attributes . EXPANDED , attributes . ROOT_ITEM , attributes . SELECTED ] ; }
Return the attributes we handle as getters/setters
 @returns {Array} The attributes in an array
Return the attributes we handle as getters / setters @returns { Array } The attributes in an array