code: public void addRow(Component component) {
  
          Component actualComponent = component == null ? m_newComponentFactory.get() : component;
          I_CmsEditableGroupRow row = m_rowBuilder.buildRow(this, actualComponent);
          m_container.addComponent(row);
          updatePlaceholder();
          updateButtonBars();
          updateGroupValidation();
      }
docs: Adds a row for the given component at the end of the group.
  
  @param component the component to wrap in the row to be added