Add typed wrapper functions to delegate classes.

lib/src/subscription_stream.dart

 // Copyright (c) 2015, 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.
 
 import 'dart:async';
 
 import "delegate/stream_subscription.dart";
 
 /// A [Stream] adapter for a [StreamSubscription].
 ///
@@ skipping 50 matching lines @@
 }
 
 /// Subscription wrapper that cancels on error.
 ///
 /// Used by [SubscriptionStream] when forwarding a subscription
 /// created with `cancelOnError` as `true` to one with (assumed)
 /// `cancelOnError` as `false`. It automatically cancels the
 /// source subscription on the first error.
 class _CancelOnErrorSubscriptionWrapper<T>
     extends DelegatingStreamSubscription<T> {
-  _CancelOnErrorSubscriptionWrapper(StreamSubscription subscription)
+  _CancelOnErrorSubscriptionWrapper(StreamSubscription<T> subscription)
       : super(subscription);
 
   void onError(Function handleError) {
     // Cancel when receiving an error.
     super.onError((error, StackTrace stackTrace) {
       var cancelFuture = super.cancel();
       if (cancelFuture != null) {
         // Wait for the cancel to complete before sending the error event.
         cancelFuture.whenComplete(() {
           if (handleError is ZoneBinaryCallback) {
             handleError(error, stackTrace);
           } else {
             handleError(error);
           }
         });
       } else {
         if (handleError is ZoneBinaryCallback) {
           handleError(error, stackTrace);
         } else {
           handleError(error);
         }
       }
     });
   }
 }