Wrapping leaf nodes in non polymer elements

runtime/observatory/lib/src/repositories/notification.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
+
+part of repositories;
+
+class NotificationChangeEvent implements M.NotificationChangeEvent {
+  final NotificationRepository repository;
+  NotificationChangeEvent(this.repository);
+}
+
+class NotificationRepository implements M.NotificationRepository {
+  final List<M.Notification> _list = new List<M.Notification>();
+
+  final StreamController<M.NotificationChangeEvent> _onChange;
+  final Stream<M.NotificationChangeEvent> onChange;
+
+  void add(M.Notification notification) {
+    _list.add(notification);
+    _onChange.add(new NotificationChangeEvent(this));
+  }
+
+  Iterable<M.Notification> list() => _list;
+
+  void delete(M.Notification notification) {
+    if (_list.remove(notification))
+    _onChange.add(new NotificationChangeEvent(this));
+  }
+
+  void deleteAll() {
+    if (_list.isNotEmpty) {
+      _list.clear();
+      _onChange.add(new NotificationChangeEvent(this));
+    }
+  }
+
+  factory NotificationRepository() {
+    var controller = new StreamController<M.NotificationChangeEvent>();
+    var stream = controller.stream.asBroadcastStream();
+    return new NotificationRepository._(controller, stream);
+  }
+  NotificationRepository._(this._onChange, this.onChange);
+}