Roll Observatory packages and add a roll script

packages/web_components/test/location_wrapper_test.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.
+
+library template_wrappers_test;
+
+import 'dart:html';
+import 'package:unittest/html_config.dart';
+import 'package:unittest/unittest.dart';
+
+main() {
+  useHtmlConfiguration();
+
+  test('OK to access location with platform.js', () {
+    expect(window.location.toString(), window.location.href);
+  });
+}