anchor.diff:          return ListView(
             padding: const EdgeInsets.all(8),
             children: <Widget>[
  +            _UserInfoCard(user),
               _EmailPasswordForm(),
               _EmailLinkSignInSection(),
               _AnonymouslySignInSection(),
  
positive.code:   // Example code for sign out.
    Future<void> _signOut() async {
      await _auth.signOut();
    }
  }
  
  
negative.code: }
  
  class _SignInPageState extends State<SignInPage> {
    User user;
  
    @override
    void initState() {
      _auth.userChanges().listen((event) => setState(() => user = event));
      super.initState();
    }
  
    @override
    Widget build(BuildContext context) {
      return Scaffold(
  