Add a basic popup menu implementation to stocks2

sky/examples/stocks2/lib/stock_menu.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 'package:sky/framework/fn2.dart';
 import 'package:sky/framework/components2/popup_menu.dart';
 import 'package:sky/framework/components2/checkbox.dart';
 import 'package:sky/framework/theme/view_configuration.dart';
 
 class StockMenu extends Component {
-  static final Style _style = new Style('''
-    position: absolute;
-    right: 8px;
-    top: ${8 + kStatusBarHeight}px;''');
+  // static final Style _style = new Style('''
+  //   position: absolute;
+  //   right: 8px;
+  //   top: ${8 + kStatusBarHeight}px;''');
 
   PopupMenuController controller;
 
   StockMenu({Object key, this.controller, this.autorefresh: false, this.onAutorefreshChanged}) : super(key: key);
 
   final bool autorefresh;
   final ValueChanged onAutorefreshChanged;
 
-  static FlexBoxParentData _flex1 = new FlexBoxParentData()..flex = 1;
-
   UINode build() {
     var checkbox = new Checkbox(
       checked: this.autorefresh,
       onChanged: this.onAutorefreshChanged
     );
 
-    return new StyleNode(
-      new PopupMenu(
-        controller: controller,
-        items: [
-          [new Text('Add stock')],
-          [new Text('Remove stock')],
-          [new ParentDataNode(new Text('Autorefresh'), _flex1), checkbox],
-        ],
-        level: 4),
-        _style
+    return new PopupMenu(
+      controller: controller,
+      items: [
+        [new Text('Add stock')],
+        [new Text('Remove stock')],
+        // [new FlexExpandingChild(new Text('Autorefresh')), checkbox],
+      ],
+      level: 4
     );
   }
 }