Add "growable" parameter to List.filled constructor.

sdk/lib/core/list.dart

 // 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.
 
 part of dart.core;
 
 /**
  * An indexable collection of objects with a length.
  *
  * Subclasses of this class implement different kinds of lists.
@@ skipping 64 matching lines @@
    * The [length] must not be negative or null, if it is provided.
    */
   external factory List([int length]);
 
   /**
    * Creates a fixed-length list of the given length, and initializes the
    * value at each position with [fill]:
    *
    *     new List<int>.filled(3, 0); // [0, 0, 0]
    *
-   * The [length] must not be negative or null.
+   * The [length] must be a non-negative integer.
+   *
+   * If the list is growable, changing its length will not initialize new
+   * entries with [fill]. After being created and filled, the list is
+   * no different from any other growable or fixed-length list
+   * created using [List].
    */
-  external factory List.filled(int length, E fill);
+  external factory List.filled(int length, E fill, {bool growable: false});
 
   /**
    * Creates a list containing all [elements].
    *
    * The [Iterator] of [elements] provides the order of the elements.
    *
    * This constructor returns a growable list when [growable] is true;
    * otherwise, it returns a fixed-length list.
    */
   external factory List.from(Iterable elements, { bool growable: true });
@@ skipping 368 matching lines @@
    * as values. The `Map.keys` [Iterable] iterates the indices of this list
    * in numerical order.
    *
    *     List<String> words = ['fee', 'fi', 'fo', 'fum'];
    *     Map<int, String> map = words.asMap();
    *     map[0] + map[1];   // 'feefi';
    *     map.keys.toList(); // [0, 1, 2, 3]
    */
   Map<int, E> asMap();
 }