code: public Span addContent(Row row, String label) {
          Span cell = new Span();
          cell.addChild(CWFUtil.getTextComponent(label));
          row.addChild(cell);
          return cell;
      }
docs: Adds a cell with the specified content to the grid row.
  
  @param row List row.
  @param label Content for cell. Auto-detects type of content.
  @return Newly created cell.