Add typed wrapper functions to delegate classes.

lib/src/typed/stream_subscription.dart

+// Copyright (c) 2016, 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';
+
+class TypeSafeStreamSubscription<T> implements StreamSubscription<T> {
+  final StreamSubscription _subscription;
+
+  bool get isPaused => _subscription.isPaused;
+
+  TypeSafeStreamSubscription(this._subscription);
+
+  void onData(void handleData(T data)) {
+    _subscription.onData((data) => handleData(data as T));
+  }
+
+  void onError(Function handleError) {
+    _subscription.onError(handleError);
+  }
+
+  void onDone(void handleDone()) {
+    _subscription.onDone(handleDone);
+  }
+
+  void pause([Future resumeFuture]) {
+    _subscription.pause(resumeFuture);
+  }
+
+  void resume() {
+    _subscription.resume();
+  }
+
+  Future cancel() => _subscription.cancel();
+  Future asFuture([futureValue]) => _subscription.asFuture(futureValue);

[Lasse Reichstein Nielsen, 2016/04/08 09:20:29]

Could be
 Future<S> asFuture<S>([S futureValue])
if you want to type it.

[nweiz, 2016/04/11 20:26:16]

Strong mode won't let us add typing that's not there in the superclass. And this
type isn't public anyway, so it wouldn't do much good.

+}