Rationalize Dart mojo and sky package structure

sky/sdk/lib/framework/components/floating_action_button.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 '../fn.dart';
 import '../theme/colors.dart';
 import 'ink_well.dart';
 import 'material.dart';
 
 class FloatingActionButton extends Component {
@@ skipping 27 matching lines @@
     if (content != null)
       children.add(content);
 
     return new Material(
       content: new Container(
         style: _style,
         children: [new StyleNode(new InkWell(children: children), _clipStyle)]),
       level: level);
   }
 }