Converted Observatory class-tree element

runtime/observatory/tests/observatory_ui/mocks/repositories/instance.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 mocks;
+
+typedef Future<M.Instance> InstanceRepositoryMockCallback(String id);
+
+class InstanceRepositoryMock implements M.InstanceRepository {
+  final InstanceRepositoryMockCallback _get;
+
+  InstanceRepositoryMock({InstanceRepositoryMockCallback getter})
+    : _get = getter;
+
+  Future<M.Instance> get(String id){
+    if (_get != null) {
+      return _get(id);
+    }
+    return new Future.value(null);
+  }
+}