Fix some strong mode issues in the core libraries.

sdk/lib/async/stream.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.
 
 part of dart.async;
 
 // -------------------------------------------------------------------
 // Core Stream types
 // -------------------------------------------------------------------
 
@@ skipping 1296 matching lines @@
       if (onTimeout == null) {
         timeout = () {
           controller.addError(
               new TimeoutException("No stream event", timeLimit), null);
         };
       } else {
         // TODO(floitsch): the return type should be 'void', and the type
         // should be inferred.
         var registeredOnTimeout =
             zone.registerUnaryCallback<dynamic, EventSink<T>>(onTimeout);
-        _ControllerEventSinkWrapper wrapper =
-            new _ControllerEventSinkWrapper(null);
+        var wrapper = new _ControllerEventSinkWrapper<T>(null);
         timeout = () {
           wrapper._sink = controller; // Only valid during call.
           zone.runUnaryGuarded(registeredOnTimeout, wrapper);
           wrapper._sink = null;
         };
       }
 
       subscription = this.listen(onData, onError: onError, onDone: onDone);
       timer = zone.createTimer(timeLimit, timeout);
     }
@@ skipping 460 matching lines @@
   }
 
   void addError(error, [StackTrace stackTrace]) {
     _sink.addError(error, stackTrace);
   }
 
   void close() {
     _sink.close();
   }
 }