code: @Override
      public void renderHead(final Component _component,
                             final IHeaderResponse _response)
      {
          super.renderHead(_component, _response);
          _response.render(AbstractEFapsHeaderItem.forJavaScript(AjaxFieldUpdateBehavior.JS));
      }
docs: Render to the web response the eFapsContentReference.
  
  @param _response Response object