Modernize the package's style.

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.
 
-library async.subscription_stream;
-
 import 'dart:async';
 
 import "delegate/stream_subscription.dart";
 
 /// A [Stream] adapter for a [StreamSubscription].
 ///
 /// This class allows a `StreamSubscription` to be treated as a `Stream`.
 ///
 /// The subscription is paused until the stream is listened to,
 /// then it is resumed and the events are passed on to the
@@ skipping 75 matching lines @@
       } else {
         if (handleError is ZoneBinaryCallback) {
           handleError(error, stackTrace);
         } else {
           handleError(error);
         }
       }
     });
   }
 }