instance property Null safety
The current AutomatedTestWidgetsFlutterBinding, if one has been created.
The binding must be initialized before using this getter. If you need the binding to be constructed before calling testWidgets, you can ensure a binding has been constructed by calling the TestWidgetsFlutterBinding.ensureInitialized function.
static AutomatedTestWidgetsFlutterBinding get instance => BindingBase.checkInstance(_instance);