Fix all the components to pick the right colours from the theme.

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

Index: sky/sdk/example/stocks/lib/main.dart
diff --git a/sky/sdk/example/stocks/lib/main.dart b/sky/sdk/example/stocks/lib/main.dart
index 504dcf5b808f8bb61bd1316fbd3817f108abae76..8cf2f815e157391919207f3f7c1798b7ca142d29 100644
--- a/sky/sdk/example/stocks/lib/main.dart
+++ b/sky/sdk/example/stocks/lib/main.dart
@@ -3,7 +3,9 @@
 // found in the LICENSE file.
 
 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/default_text_style.dart';
 import 'package:sky/widgets/navigator.dart';
 import 'package:sky/widgets/theme.dart';
 import 'package:sky/widgets/widget.dart';
@@ -80,7 +82,10 @@ class StocksApp extends App {
 
     return new Theme(
       data: theme,
-        child: new Navigator(_navigationState)
+        child: new DefaultTextStyle(
+          style: typography.error, // if you see this, you've forgotten to correctly configure the text style!
+          child: new Navigator(_navigationState)
+        )
      );
    }
 }