Modernize the package's style.

lib/src/delegate/stream_subscription.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.
 
-library async.delegate.stream_subscription;
-
 import 'dart:async';
 
 /// Simple delegating wrapper around a [StreamSubscription].
 ///
 /// Subclasses can override individual methods.
 class DelegatingStreamSubscription<T> implements StreamSubscription<T> {
   final StreamSubscription _source;
 
   /// Create delegating subscription forwarding calls to [sourceSubscription].
   DelegatingStreamSubscription(StreamSubscription sourceSubscription)
@@ skipping 18 matching lines @@
   void resume() {
     _source.resume();
   }
 
   Future cancel() => _source.cancel();
 
   Future asFuture([futureValue]) => _source.asFuture(futureValue);
 
   bool get isPaused => _source.isPaused;
 }