anchor.diff:        var typeParameter = element.bound;
         if (typeParameter == null) continue;
         if (typeParameter is analyzer.InterfaceType) {
  -        if (typeParameter.element.isPrivate) {
  +        if (typeParameter.element2.isPrivate) {
             errorMessages.add(
                 '${enclosingElement.fullName} features a private type parameter '
                 'bound, and cannot be stubbed.');
  
positive.code: 
    Expression _dummyValueImplementing(
        analyzer.InterfaceType dartType, Expression invocation) {
      final elementToFake = dartType.element;
      if (elementToFake.isEnum) {
        return _typeReference(dartType).property(
            elementToFake.fields.firstWhere((f) => f.isEnumConstant).name);
      } else {
  
negative.code:     } else if (type is analyzer.TypeParameterType) {
        return TypeReference((b) {
          b
            ..symbol = type.element2.name
            ..isNullable = forceNullable || typeSystem.isNullable(type);
        });
      } else {
        return referImported(
          type.getDisplayString(withNullability: false),
          _typeImport(type.element2),
        );
      }
    }
  