[Layout] Put in some guards to prevent us from reintroducing 'display' properties into the CSS.

sky/examples/stocks/lib/stock_row.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/components/ink_well.dart';
 import 'package:sky/framework/fn.dart';
+import 'package:sky/framework/layout.dart';
 import 'package:sky/framework/theme/typography.dart' as typography;
 import 'stock_arrow.dart';
 import 'stock_data.dart';
 
 class StockRow extends Component {
   static final Style _style = new Style('''
-    display: flex;
-    flex-direction: row;
     align-items: center;
     border-bottom: 1px solid #F4F4F4;
     padding-top: 16px;
     padding-left: 16px;
     padding-right: 16px;
     padding-bottom: 20px;'''
   );
 
-  static final Style _tickerStyle = new Style('''
-    flex: 1;'''
-  );
+  static final FlexBoxParentData _tickerFlex = new FlexBoxParentData()..flex = 1;
 
   static final Style _lastSaleStyle = new Style('''
     text-align: right;
     padding-right: 16px;'''
   );
 
   static final Style _changeStyle = new Style('''
     ${typography.black.caption};
     text-align: right;'''
   );
 
   Stock stock;
 
   StockRow({Stock stock}) : super(key: stock.symbol) {
     this.stock = stock;
   }
 
   UINode build() {
     String lastSale = "\$${stock.lastSale.toStringAsFixed(2)}";
 
     String changeInPrice = "${stock.percentChange.toStringAsFixed(2)}%";
     if (stock.percentChange > 0)
       changeInPrice = "+" + changeInPrice;
 
     List<UINode> children = [
       new StockArrow(
         percentChange: stock.percentChange
       ),
-      new Container(
-        key: 'Ticker',
-        style: _tickerStyle,
-        children: [new Text(stock.symbol)]
+      new ParentDataNode(
+        new Container(
+          key: 'Ticker',
+          children: [new Text(stock.symbol)]
+        ),
+        _tickerFlex
       ),
       new Container(
         key: 'LastSale',
         style: _lastSaleStyle,
         children: [new Text(lastSale)]
       ),
       new Container(
         key: 'Change',
         style: _changeStyle,
         children: [new Text(changeInPrice)]
       )
     ];
 
     return new StyleNode(new InkWell(children: children), _style);
   }
 }