anchor.diff:  import '../framework/framework_core.dart';
   import '../primitives/blocking_action_mixin.dart';
   import '../primitives/url_utils.dart';
  +// ignore_for_file: import_of_legacy_library_into_null_safe
  +
  +import '../primitives/utils.dart';
   import '../ui/label.dart';
   import 'common_widgets.dart';
   import 'file_import.dart';
  
positive.code: // Copyright 2019 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.
  
  // @dart=2.9
  
  import 'package:flutter/material.dart';
  import 'package:provider/provider.dart';
  
negative.code: }
  
  class AppSizeToolingInstructions extends StatelessWidget {
    const AppSizeToolingInstructions({Key? key}) : super(key: key);
  
    @override
    Widget build(BuildContext context) {
  