Add support for text styles.

sky/examples/stocks2/lib/stock_app.dart

Index: sky/examples/stocks2/lib/stock_app.dart
diff --git a/sky/examples/stocks2/lib/stock_app.dart b/sky/examples/stocks2/lib/stock_app.dart
index db559946e6d6c142c56c9f094102afa0f080af6c..693bed61d561597a6e60f7cd7e9a12313d4133e5 100644
--- a/sky/examples/stocks2/lib/stock_app.dart
+++ b/sky/examples/stocks2/lib/stock_app.dart
@@ -5,7 +5,9 @@
 import 'package:sky/framework/app.dart';
 import 'package:sky/framework/editing2/input.dart';
 import 'package:sky/framework/rendering/box.dart';
+import 'package:sky/framework/rendering/paragraph.dart';
 import 'package:sky/framework/theme2/colors.dart' as colors;
+import 'package:sky/framework/theme2/typography.dart' as typography;
 import 'package:sky/framework/widgets/drawer.dart';
 import 'package:sky/framework/widgets/drawer_header.dart';
 import 'package:sky/framework/widgets/floating_action_button.dart';
@@ -29,9 +31,6 @@ enum StockMode { optimistic, pessimistic }
 
 class StocksApp extends App {
 
-  // static final Style _titleStyle = new Style('''
-  //   ${typography.white.title};''');
-
   List<Stock> _stocks = [];
 
   StocksApp({ RenderView renderViewOverride }) : super(renderViewOverride: renderViewOverride) {
@@ -158,7 +157,7 @@ class StocksApp extends App {
         left: new IconButton(
           icon: 'navigation/menu_white',
           onGestureTap: (_) => _drawerController.toggle()),
-        center: new Text('Stocks'),
+        center: new Text('Stocks', style: typography.white.title),
         right: [
           new IconButton(
             icon: 'action/search_white',