Refactor fn2.dart, since it breached our 1000-line threshold.

sky/sdk/lib/framework/widgets/tool_bar.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 '../fn2.dart';
 import '../rendering/flex.dart';
+import '../theme2/shadows.dart';
 import '../theme2/view_configuration.dart';
-import '../theme2/shadows.dart';
+import 'wrappers.dart';
 
 class ToolBar extends Component {
 
   ToolBar({
     String key,
     this.left,
     this.center,
     this.right,
     this.backgroundColor
   }) : super(key: key);
@@ skipping 23 matching lines @@
       ),
       padding: new EdgeDims.symmetric(horizontal: 8.0),
       decoration: new BoxDecoration(
         backgroundColor: backgroundColor,
         boxShadow: Shadow[2]
       )
     );
   }
 
 }