anchor.diff:   *
    * All methods that can modify the list will throw an [UnsupportedError].
    */
  -class UnmodifiableUint8List extends Object with _UnmodifiableListMixin<int> implements Uint8List {
  +class UnmodifiableUint8List implements Uint8List {
   
     final Uint8List _underlyingUint8List;
   
  
positive.code:     throw new UnsupportedError(
          "Cannot modify an unmodifiable list");
    }
  }
negative.code: 
    @override
    noSuchMethod(Invocation invocation) => reflect(_underlyingUint8List).delegate(invocation);
  
    /** This operation is not supported by an unmodifiable list. */
    void operator []=(int index, E value) {
  