anchor.diff:  
   import 'package:flutter/rendering.dart';
   import 'package:flutter/services.dart';
  +import 'package:meta/meta.dart';
   
   import 'debug.dart';
   import 'framework.dart';
  
positive.code:   /// The bundle to use as a default.
    final AssetBundle bundle;
  
    /// The bundle from the closest instance of this class that encloses the given context.
    static AssetBundle of(BuildContext context) {
      DefaultAssetBundle result = context.inheritFromWidgetOfExactType(DefaultAssetBundle);
      return result?.bundle;
    }
  
    @override
  
negative.code: ///
  /// By default, asset image will load the image from the closest enclosing
  /// [DefaultAssetBundle].
  ///
  /// To get an asset bundle that automatically performs
  /// pixel-density-aware asset resolution, use a [MaterialApp],
  /// [WidgetsApp], or [AssetVendor] widget, which introduce a
  /// suitably-configured [DefaultAssetBundle] widget.
  class AssetImage extends StatelessWidget {
    /// Creates an [AssetImage].
    ///
    /// The `name` argument must not be null.
    // Don't add asserts here unless absolutely necessary, since it will
    // require removing the const constructor, which is an API change.
    const AssetImage({
      Key key,
      @required this.name,
      this.bundle,
      this.width,
      this.height,
  