Use internal const-constructor.

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 1477 matching lines @@
 
   /** Close the sink. No further events can be added after closing. */
   void close();
 }
 
 
 /** [Stream] wrapper that only exposes the [Stream] interface. */
 class StreamView<T> extends Stream<T> {
   final Stream<T> _stream;
 
-  StreamView(this._stream);
+  const StreamView(this._stream) : super._internal();

[kevmoo, 2016/02/11 21:19:56]

Please update changelog, too

[Lasse Reichstein Nielsen, 2016/02/11 22:04:49]

Consider making the public parameter name be "stream" instead of "_stream":
  const StreamView(Stream<T> stream): _stream = stream, super._internal();

[floitsch, 2016/02/12 19:29:16]

Done.

[floitsch, 2016/02/12 19:29:16]

Done.

 
   bool get isBroadcast => _stream.isBroadcast;
 
   Stream<T> asBroadcastStream({void onListen(StreamSubscription subscription),
                                void onCancel(StreamSubscription subscription)})
       => _stream.asBroadcastStream(onListen: onListen, onCancel: onCancel);
 
   StreamSubscription<T> listen(void onData(T value),
                                { Function onError,
                                  void onDone(),
@@ skipping 291 matching lines @@
 class _ControllerEventSinkWrapper<T> implements EventSink<T> {
   EventSink _sink;
   _ControllerEventSinkWrapper(this._sink);
 
   void add(T data) { _sink.add(data); }
   void addError(error, [StackTrace stackTrace]) {
     _sink.addError(error, stackTrace);
   }
   void close() { _sink.close(); }
 }