anchor.diff:                case _MenuOptions.addCookie:
                   _onAddCookie(controller.data!);
                   break;
  +              case _MenuOptions.setCookie:
  +                _onSetCookie(controller.data!);
  +                break;
                 case _MenuOptions.removeCookie:
                   _onRemoveCookie(controller.data!);
                   break;
  
positive.code:             const PopupMenuItem<_MenuOptions>(
                value: _MenuOptions.addCookie,
                child: Text('Add cookie'),
              ),
              const PopupMenuItem<_MenuOptions>(
                value: _MenuOptions.removeCookie,
  
negative.code:     );
    }
  
    Future<void> _onSetCookie(WebViewController controller) async {
      await cookieManager.setCookie(
        const WebViewCookie(name: 'foo', value: 'bar', domain: 'flutter.dev'),
      );
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(
          content: Text('Custom cookie is set.'),
        ),
      );
    }
  
    Future<void> _onRemoveCookie(WebViewController controller) async {
      await controller.runJavascript(
          'document.cookie="FirstName=John; expires=Thu, 01 Jan 1970 00:00:00 UTC" ');
  