Roll Observatory packages and add a roll script

packages/unittest/test/nested_groups_setup_teardown_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 unittest.nested_groups_setup_teardown_test;
+
+import 'dart:async';
+
+import 'package:unittest/unittest.dart';
+
+import 'package:metatest/metatest.dart';
+
+void main() => initTests(_test);
+
+void _test(message) {
+  initMetatest(message);
+
+  expectTestsPass('nested groups setup/teardown', () {
+    StringBuffer s = new StringBuffer();
+    group('level 1', () {
+      setUp(makeDelayedSetup(1, s));
+      group('level 2', () {
+        setUp(makeImmediateSetup(2, s));
+        tearDown(makeDelayedTeardown(2, s));
+        group('level 3', () {
+          group('level 4', () {
+            setUp(makeDelayedSetup(4, s));
+            tearDown(makeImmediateTeardown(4, s));
+            group('level 5', () {
+              setUp(makeImmediateSetup(5, s));
+              group('level 6', () {
+                tearDown(makeDelayedTeardown(6, s));
+                test('inner', () {});
+              });
+            });
+          });
+        });
+      });
+    });
+    test('after nest', () {
+      expect(s.toString(), "l1 U l2 U l4 U l5 U l6 D l4 D l2 D ");
+    });
+  });
+}
+
+Function makeDelayedSetup(int index, StringBuffer s) => () {
+  return new Future.delayed(new Duration(milliseconds: 1), () {
+    s.write('l$index U ');
+  });
+};
+
+Function makeDelayedTeardown(int index, StringBuffer s) => () {
+  return new Future.delayed(new Duration(milliseconds: 1), () {
+    s.write('l$index D ');
+  });
+};
+
+Function makeImmediateSetup(int index, StringBuffer s) => () {
+  s.write('l$index U ');
+};
+
+Function makeImmediateTeardown(int index, StringBuffer s) => () {
+  s.write('l$index D ');
+};