Roll Observatory packages and add a roll script

packages/polymer/test/build/static_clean_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 args;
+library polymer.test.build.static_clean_test;
 
-export 'src/arg_parser.dart';
-export 'src/arg_results.dart' hide newArgResults;
-export 'src/option.dart' hide newOption;
+import 'package:polymer/builder.dart';
+
+_unused() => build;
+
+void main() {
+  // Check that builder.dart is statically clean. Nothing to do.
+}