Cleanup sky/sdk/examples

sky/sdk/example/stocks/lib/stock_settings.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/checkbox.dart';
 import 'package:sky/widgets/flat_button.dart';
 import 'package:sky/widgets/dialog.dart';
 import 'package:sky/widgets/icon_button.dart';
@@ skipping 96 matching lines @@
               _handleStockModeChanged(true);
               navigator.pop();
             }
           ),
         ]
       ));
     }
     return new Stack(layers);
   }
 }