anchor.diff:      expect(find.byType(Navigator), findsOneWidget);
       expect(find.byType(PerformanceOverlay), findsNothing);
       expect(find.byType(CheckedModeBanner), findsNothing);
  +    WidgetsApp.debugAllowBannerOverride = true; // restore to default value
     });
   
     testWidgets('debugAllowBannerOverride true', (WidgetTester tester) async {
  +    WidgetsApp.debugAllowBannerOverride = false;
       expect(WidgetsApp.showPerformanceOverlayOverride, false);
       expect(WidgetsApp.debugAllowBannerOverride, false);
       WidgetsApp.debugAllowBannerOverride = true;
  
positive.code:     expect(find.byType(Navigator), findsOneWidget);
      expect(find.byType(PerformanceOverlay), findsOneWidget);
      expect(find.byType(CheckedModeBanner), findsOneWidget);
    });
  
    testWidgets('showPerformanceOverlayOverride false', (WidgetTester tester) async {
      expect(WidgetsApp.showPerformanceOverlayOverride, true);
      WidgetsApp.showPerformanceOverlayOverride = false;
      await pumpApp(tester);
  
negative.code: // Copyright 2014 The Flutter Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  import 'package:flutter/widgets.dart';
  import 'package:flutter_test/flutter_test.dart';
  