anchor.diff:  // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
   // for details. All rights reserved. Use of this source code is governed by a
   // BSD-style license that can be found in the LICENSE file.
  -
  -// @dart = 2.5
   
   // Patch file for dart:math library.
   import 'dart:_foreign_helper' show JS;
  
positive.code: 
  @patch
  class Random {
    static Random _secureRandom;
  
    @patch
    factory Random([int seed]) =>
        (seed == null) ? const _JSRandom() : new _Random(seed);
  
    @patch
  
negative.code:     }
      _buffer.setUint32(0, 0);
      int start = 4 - byteCount;
      int randomLimit = pow(256, byteCount) as int;
      while (true) {
        _getRandomBytes(start, byteCount);
        // The getUint32 method is big-endian as default.
  