_init(node) {
        this._node = node;
        this._cells = [];
        this._node.children.forEach(cellNode => {
            const cell = new Cell(this, cellNode);
            this._cells[cell.columnNumber()] = cell;
        });
        this._node.children = this._cells;
    }
Initialize the row node.
@param {{}} node - The row node.
@returns {undefined}
@private