anchor.diff:    bool _useLightTheme = true;
     bool _showPerformanceOverlay = false;
     bool _checkerboardRasterCacheImages = false;
  +  double _timeDilation = 1.0;
  +  TargetPlatform _platform = defaultTargetPlatform;
   
  -  TargetPlatform platform = defaultTargetPlatform;
  +  Timer _timeDilationTimer;
  +
  +  @override
  +  void initState() {
  +    _timeDilation = timeDilation;
  +    super.initState();
  +  }
  +
  +  @override
  +  void dispose() {
  +    _timeDilationTimer?.cancel();
  +    _timeDilationTimer = null;
  +    super.dispose();
  +  }
   
     @override
     Widget build(BuildContext context) {
  
positive.code: // Copyright 2015 The Chromium 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/foundation.dart' show defaultTargetPlatform;
  import 'package:flutter/material.dart';
  
negative.code:     return new MaterialApp(
        title: 'Flutter Gallery',
        color: Colors.grey[500],
        theme: (_useLightTheme ? _kGalleryLightTheme : _kGalleryDarkTheme).copyWith(platform: _platform),
        showPerformanceOverlay: _showPerformanceOverlay,
        checkerboardRasterCacheImages: _checkerboardRasterCacheImages,
        routes: _kRoutes,
  