Roll Observatory packages and add a roll script

packages/utf/test/utf_test.dart

+// Copyright (c) 2012, 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 utf.utf_test;
+
+import "package:expect/expect.dart";
+import "package:utf/utf.dart";
+
+main() {
+  String str = new String.fromCharCodes([0x1d537]);
+  // String.codeUnits gives 16-bit code units, but stringToCodepoints gives
+  // back the original code points.
+  Expect.listEquals([0xd835, 0xdd37], str.codeUnits);
+  Expect.listEquals([0x1d537], stringToCodepoints(str));
+}