Make core libraries use generic method syntax.

sdk/lib/async/broadcast_stream_controller.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.async;
 
 class _BroadcastStream<T> extends _ControllerStream<T> {
   _BroadcastStream(_StreamControllerLifecycle<T> controller)
       : super(controller);
 
@@ skipping 522 matching lines @@
   void pause([Future resumeSignal]) {
     if (resumeSignal != null) resumeSignal.then(_resume);
     _pauseCount++;
   }
   void resume() { _resume(null); }
   void _resume(_) {
     if (_pauseCount > 0) _pauseCount--;
   }
   Future cancel() { return new _Future.immediate(null); }
   bool get isPaused => _pauseCount > 0;
-  Future/*<E>*/ asFuture/*<E>*/([Object/*=E*/ value]) => new _Future/*<E>*/();
+  Future<E> asFuture<E>([E value]) => new _Future<E>();
 }