Fix comment on int.toUnsigned()

sdk/lib/core/int.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 arbitrarily large integer.
  *
  * **Note:** When compiling to JavaScript, integers are
@@ skipping 152 matching lines @@
    *      (-3).bitLength == 2;  // 11111101
    *      (-4).bitLength == 2;  // 11111100
    */
   int get bitLength;
 
   /**
    * Returns the least significant [width] bits of this integer as a
    * non-negative number (i.e. unsigned representation).  The returned value has
    * zeros in all bit positions higher than [width].
    *
-   *     (-1).toUnsigned(5) == 32   // 11111111  ->  00011111
+   *     (-1).toUnsigned(5) == 31   // 11111111  ->  00011111
    *
    * This operation can be used to simulate arithmetic from low level languages.
    * For example, to increment an 8 bit quantity:
    *
    *     q = (q + 1).toUnsigned(8);
    *
    * `q` will count from `0` up to `255` and then wrap around to `0`.
    *
    * If the input fits in [width] bits without truncation, the result is the
    * same as the input.  The minimum width needed to avoid truncation of `x` is
@@ skipping 127 matching lines @@
    *     var value = int.parse(text, onError: (source) => null);
    *     if (value == null) ... handle the problem
    *
    * The [onError] function is only invoked if [source] is a [String]. It is
    * not invoked if the [source] is, for example, `null`.
    */
   external static int parse(String source,
                             { int radix,
                               int onError(String source) });
 }