Roll Observatory packages and add a roll script

packages/initialize/test/foo.dart

 // Copyright (c) 2015, 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 web_components.init;
+@initializeTracker
+library initialize.test.foo;
 
-import 'dart:async';
-import 'src/init.dart';
+import 'package:initialize/src/initialize_tracker.dart';
 
-Future main() => initWebComponents();
+@initializeTracker
+class Foo {}
+
+@initializeTracker
+fooBar() {}
+
+@initializeTracker
+foo() {}