anchor.diff:  }
   
   Type getRuntimeType(object) {
  -  Rti rti = _instanceFunctionType(object) ?? instanceType(object);
  +  Rti rti = _instanceFunctionType(object) ?? _nonClosureInstanceType(object);
     return _createRuntimeType(rti);
   }
   
  
positive.code: 
  bool isFutureOrType(Rti t) => Rti._getKind(t) == Rti.kindFutureOr;
  
  bool isGenericFunctionKind(Rti t) => Rti._getKind(t) == Rti.kindGenericFunction;
  
  bool isGenericFunctionTypeParameter(Rti t) =>
  
negative.code:     }
    }
  
    if (isEitherFunctionKind(t)) {
      return _isFunctionSubtype(universe, s, sEnv, t, tEnv);
    }
  
    if (isEitherFunctionKind(s)) {
      return isFunctionType(t);
    }
  
  