anchor.diff:      if (modelParent == null)
         return;
   
  -    yield* _findModels<T>(modelParent, aspect);
  +    _findModels<T>(modelParent, aspect, results);
     }
   
     /// Makes [context] dependent on the specified [aspect] of an [InheritedModel]
  
positive.code: 
    // The [result] will be a list of all of context's type T ancestors concluding
    // with the one that supports the specified model [aspect].
    static Iterable<InheritedElement> _findModels<T extends InheritedModel<Object>>(BuildContext context, Object aspect) sync* {
      final InheritedElement model = context.ancestorInheritedElementForWidgetOfExactType(T);
      if (model == null)
        return;
  
      yield model;
  
      assert(model.widget is T);
      final T modelWidget = model.widget;
  
negative.code: 
      // Create a dependency on all of the type T ancestor models up until
      // a model is found for which isSupportedAspect(aspect) is true.
      final List<InheritedElement> models = <InheritedElement>[];
      _findModels<T>(context, aspect, models);
      if (models.isEmpty) {
        return null;
      }
  