Adding Angular and dependent packages for testing

third_party/pkg/js/lib/src/wrapping/translator.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 js.wrapping;
+
+class Translator<E> {
+  final Mapper<dynamic, E> fromJs;
+  final Mapper<E, dynamic> toJs;
+
+  Translator(this.fromJs, this.toJs);
+}
+
+class TranslatorForSerializable<E extends Serializable>
+    implements Translator<E> {
+  Mapper<dynamic, E> _fromJs;
+  Mapper<E, dynamic> _toJs;
+
+  TranslatorForSerializable(Mapper<dynamic, E> fromJs, {mapOnlyNotNull: true}) {
+    this._fromJs = (o) => mapOnlyNotNull ? mapNotNull(o, fromJs) : fromJs(o);
+    this._toJs = (E s) => s != null ? s.toJs() : null;
+  }
+
+  Mapper<dynamic, E> get fromJs => this._fromJs;
+  void set fromJs(v) => throw "final";
+
+  Mapper<E, dynamic> get toJs => this._toJs;
+  void set toJs(v) => throw "final";
+}