Roll Observatory packages and add a roll script

packages/path/test/browser_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.
+
+import 'dart:html';
+
+import 'package:unittest/unittest.dart';
+import 'package:unittest/html_config.dart';
+import 'package:path/path.dart' as path;
+
+main() {
+  useHtmlConfiguration();
+
+  group('new Context()', () {
+    test('uses the window location if root and style are omitted', () {
+      var context = new path.Context();
+      expect(context.current,
+          Uri.parse(window.location.href).resolve('.').toString());
+    });
+
+    test('uses "." if root is omitted', () {
+      var context = new path.Context(style: path.Style.platform);
+      expect(context.current, ".");
+    });
+
+    test('uses the host platform if style is omitted', () {
+      var context = new path.Context();
+      expect(context.style, path.Style.platform);
+    });
+  });
+
+  test('Style.platform is url', () {
+    expect(path.Style.platform, path.Style.url);
+  });
+
+  test('current', () {
+    expect(
+        path.current, Uri.parse(window.location.href).resolve('.').toString());
+  });
+}