Converted Observatory nav-notify element

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 =
+      new StreamController<M.NotificationChangeEvent>.broadcast();
+  Stream<M.NotificationChangeEvent> get onChange => _onChange.stream;
+
+  void add(M.Notification notification) {
+    _list.add(notification);
+    _notify();
+  }
+
+  Iterable<M.Notification> list() => _list;
+
+  void delete(M.Notification notification) {
+    if (_list.remove(notification))
+    _notify();
+  }
+
+  void deleteAll() {
+    if (_list.isNotEmpty) {
+      _list.clear();
+      _notify();
+    }
+  }
+
+  NotificationRepository();
+
+  void _notify() {
+    _onChange.add(new NotificationChangeEvent(this));
+  }
+}