Roll Observatory packages and add a roll script

packages/initialize/test/init_method_test.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 initialize.init_method_test;
+
+import 'package:initialize/initialize.dart';
+import 'package:unittest/unittest.dart';
+import 'package:unittest/compact_vm_config.dart';
+
+int calledFoo = 0;
+int calledBar = 0;
+
+main() {
+  useCompactVMConfiguration();
+
+  // Run all initializers.
+  run().then((_) {
+    test('initMethod annotation invokes functions once', () {
+      expect(calledFoo, 1);
+      expect(calledBar, 1);
+      // Re-run all initializers, should be a no-op.
+      return run().then((_) {
+        expect(calledFoo, 1);
+        expect(calledBar, 1);
+      });
+    });
+  });
+}
+
+@initMethod
+foo() => calledFoo++;
+
+@initMethod
+bar() => calledBar++;