Make hashCode a getter and not a method.

lib/isolate/base.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.
 
 class IsolateSpawnException implements Exception {
   const IsolateSpawnException(String this._s);
   String toString() => "IsolateSpawnException: '$_s'";
   final String _s;
 }
 
@@ skipping 74 matching lines @@
   /**
    * Tests whether [other] is a [SendPort] pointing to the same
    * [ReceivePort] as this one.
    */
   bool operator==(var other);
 
   /**
    * Returns an immutable hash code for this send port that is
    * consistent with the == operator.
    */
-  int hashCode();
+  int get hashCode;
 
 }
 
 /**
  * [ReceivePort]s, together with [SendPort]s, are the only means of
  * communication between isolates. [ReceivePort]s have a [:toSendPort:] method
  * which returns a [SendPort]. Any message that is sent through this [SendPort]
  * is delivered to the [ReceivePort] it has been created from. There, they are
  * dispatched to the callback that has been registered on the receive port.
  *
@@ skipping 33 matching lines @@
 // TODO(kasperl): Document this.
 abstract class SendPortSync {
 
   callSync(var message);
 
 }
 
 class _ReceivePortFactory {
   external factory ReceivePort();
 }