SkyDemo should launch demos in their own windows

sky/sdk/example/demo_launcher/lib/main.dart

 // Copyright 2015 The Chromium Authors. 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:sky';
 
 import 'package:mojom/intents/intents.mojom.dart';
+import 'package:sky/mojo/activity.dart' as activity;
 import 'package:sky/mojo/asset_bundle.dart';
 import 'package:sky/mojo/shell.dart' as shell;
 import 'package:sky/painting/box_painter.dart';
 import 'package:sky/theme/colors.dart' as colors;
 import 'package:sky/theme/typography.dart' as typography;
 import 'package:sky/widgets/basic.dart';
 import 'package:sky/widgets/card.dart';
 import 'package:sky/widgets/fixed_height_scrollable.dart';
 import 'package:sky/widgets/flat_button.dart';
 import 'package:sky/widgets/material.dart';
@@ skipping 13 matching lines @@
 void launch(String relativeUrl, String bundle) {
   Uri url = Uri.base.resolve(relativeUrl);
 
   ActivityManagerProxy activityManager = new ActivityManagerProxy.unbound();
   ComponentName component = new ComponentName()
     ..packageName = 'org.domokit.sky.demo'
     ..className = 'org.domokit.sky.demo.SkyDemoActivity';
   Intent intent = new Intent()
     ..action = 'android.intent.action.VIEW'
     ..component = component
+    ..flags = activity.MULTIPLE_TASK | activity.NEW_DOCUMENT
     ..url = url.toString();
 
   if (bundle != null) {
     StringExtra extra = new StringExtra()
       ..name = 'bundleName'
       ..value = bundle;
     intent.stringExtras = [extra];
   }
 
-  shell.requestService(null, activityManager);
-  activityManager.ptr.startActivity(intent);
+  activity.startActivity(intent);
 }
 
 class SkyDemo {
   String name;
   String href;
   String bundle;
   String description;
   typography.TextTheme textTheme;
   BoxDecoration decoration;
   SkyDemo({ this.name, this.href, this.bundle, this.description, this.textTheme, this.decoration });
@@ skipping 123 matching lines @@
           child: new DemoList()
         )
       )
     );
   }
 }
 
 void main() {
   runApp(new SkyHome());
 }