Improve drawer menu items

sky/sdk/lib/widgets/dialog.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/theme/colors.dart' as colors;
 import 'package:sky/widgets/basic.dart';
 import 'package:sky/widgets/default_text_style.dart';
 import 'package:sky/widgets/material.dart';
 import 'package:sky/widgets/scrollable_viewport.dart';
 import 'package:sky/widgets/theme.dart';
@@ skipping 21 matching lines @@
   /// The (optional) set of actions that are displayed at the bottom of the
   /// dialog.
   final List<Widget> actions;
 
   /// An (optional) callback that is called when the dialog is dismissed.
   final Function onDismiss;
 
   Color get _color {
     switch (Theme.of(this).brightness) {
       case ThemeBrightness.light:
-        return colors.White;
+        return colors.white;
       case ThemeBrightness.dark:
         return colors.Grey[800];
     }
   }
 
   Widget build() {
     Container mask = new Container(
       decoration: const BoxDecoration(
         backgroundColor: const Color(0x7F000000)));
 
@@ skipping 38 matching lines @@
               child: new ShrinkWrapWidth(
                 child: new ScrollableBlock(children)
               )
             )
           )
         )
       )
     ]);
   }
 }