Roll Observatory packages and add a roll script

packages/charted/test.disabled/core/object_factory_test.dart

+/*
+ * Copyright 2014 Google Inc. All rights reserved.
+ *
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file or at
+ * https://developers.google.com/open-source/licenses/bsd
+ */
+
+part of charted.test.core;
+
+class MockObject { }
+class MockCreateFailObject {
+  factory MockCreateFailObject() => null;
+}
+
+testObjectFactory() {
+  ObjectFactory factory = new ObjectFactory();
+  factory.register("mock", () => new MockObject());
+  factory.register("mockfail", () => new MockCreateFailObject());
+
+  group('ObjectFactory.create()', () {
+    test('creates an object of a registered factory', () {
+      expect(factory.create("mock"), new isInstanceOf<MockObject>());
+    });
+    test('throwsArgumentError if a factory returns null', () {
+      expect(() => factory.create("mockfail"), throwsArgumentError);
+    });
+    test('throwsArgumentError when a factory is not registered', () {
+      expect(() => factory.create("notregistered"), throwsArgumentError);
+    });
+  });
+}