anchor.diff:  
       return new Theme(
         data: theme,
  -       child: new Navigator(_navigationState)
  +        child: new Navigator(_navigationState)
        );
      }
   }
  
positive.code: // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  import 'package:sky/rendering/sky_binding.dart';
  import 'package:sky/theme/colors.dart' as colors;
  import 'package:sky/theme/theme_data.dart';
  import 'package:sky/widgets/basic.dart';
  
negative.code:     });
    }
  
    Widget build() {
  
      ThemeData theme;
      if (stockMode == StockMode.optimistic) {
  