anchor.diff:      });
       return DropdownButton(
         items: menu,
  -      icon: Flexible(
  -        child: Center(
  -          child: Icon(Icons.more_vert),
  -        ),
  -      ),
  +      underline: Container(),
  +      icon: Icon(Icons.more_vert),
         onChanged: (String selectedMenuItem) =>
             onMenuItemPressed(selectedMenuItem),
       );
  
positive.code:     if (errorText != null) {
        return Text(errorText);
      } else if (isLoading) {
        return CircularProgressIndicator();
      } else {
        return Container(
          constraints: BoxConstraints(maxHeight: 224),
          child: child,
        );
      }
  
negative.code:   Widget build(BuildContext context) {
      if (!hidden) {
        return Card(
          semanticContainer: false,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.center,
            children: <Widget>[
  