Make List.shuffle take an optional Random object to use.

runtime/lib/typed_data.dart

 // Copyright (c) 2013, 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.
 
 // patch classes for Int8List ..... Float64List and ByteData implementations.
 
 patch class Int8List {
   /* patch */ factory Int8List(int length) {
     return new _Int8Array(length);
   }
@@ skipping 392 matching lines @@
 
   void insertAll(int index, Iterable values) {
     throw new UnsupportedError(
         "Cannot insert into a non-extendable array");
   }
 
   void sort([int compare(num a, num b)]) {
     IterableMixinWorkaround.sortList(this, compare);
   }
 
-  void shuffle() {
-    IterableMixinWorkaround.shuffleList(this);
+  void shuffle([Random random]) {
+    IterableMixinWorkaround.shuffleList(this, random);
   }
 
   int indexOf(element, [int start = 0]) {
     return IterableMixinWorkaround.indexOfList(this, element, start);
   }
 
   int lastIndexOf(element, [int start = null]) {
     return IterableMixinWorkaround.lastIndexOfList(this, element, start);
   }
 
@@ skipping 2728 matching lines @@
     return value;
   }
   return object;
 }
 
 
 void _throwRangeError(int index, int length) {
   String message = "$index must be in the range [0..$length)";
   throw new RangeError(message);
 }