Effen error if a component ancestor doesn't specify a style

sky/framework/fn.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.
 
 library fn;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:sky' as sky;
 import 'reflect.dart' as reflect;
@@ skipping 421 matching lines @@
 
   void _ensureClass() {
     if (_class == null) {
       List<Style> styles = new List<Style>();
       if (style != null) {
         styles.add(style);
       }
 
       Node parent = _parent;
       while (parent != null && parent is! RenderNode) {
-        if (parent is StyleNode)
+        if (parent is StyleNode  && (parent as StyleNode).style != null)

[ojan, 2015/03/30 20:44:11]

You have two spaces after StyleNode.

           styles.add((parent as StyleNode).style);
 
         parent = parent._parent;
       }
 
       _class = styles.map((s) => s._className).join(' ');
     }
   }
 
   void _syncNode(RenderNode old) {
@@ skipping 446 matching lines @@
 
 abstract class App extends Component {
   sky.Node _host;
 
   App() : super(stateful: true) {
     _host = sky.document.createElement('div');
     sky.document.appendChild(_host);
     _scheduleComponentForRender(this);
   }
 }