anchor.diff:          '-v',
           '--release',
           '--no-pub',
  -      ]);
  +      ], environment: <String, String>{
  +        'FLUTTER_WEB': 'true',
  +      });
         final String output = '${flutterDirectory.path}/examples/flutter_gallery/build/web/main.dart.js';
         await _measureSize('flutter_gallery', output, metrics);
         return null;
  
positive.code:         '-v',
          '--release',
          '--no-pub',
        ]);
        final String output = '${flutterDirectory.path}/examples/hello_world/build/web/main.dart.js';
        await _measureSize('hello_world', output, metrics);
        return null;
  
negative.code:           '-v',
            '--release',
            '--no-pub',
          ], environment: <String, String>{
            'FLUTTER_WEB': 'true',
          });
          await _measureSize('basic_material_app', path.join(sampleDir.path, 'build/web/main.dart.js'), metrics);
        });
      });
  