Sky support for flexbox justify content

sky/examples/lib/solid_color_box.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 'dart:sky';
 import 'package:sky/framework/rendering/box.dart';
 
 class RenderSolidColorBox extends RenderDecoratedBox {
   final Size desiredSize;
   final Color backgroundColor;
 
-  RenderSolidColorBox(Color backgroundColor, { this.desiredSize: const Size.infinite() })
+  RenderSolidColorBox(Color backgroundColor, { this.desiredSize: Size.infinite })
       : backgroundColor = backgroundColor,
         super(decoration: new BoxDecoration(backgroundColor: backgroundColor));
 
   Size getIntrinsicDimensions(BoxConstraints constraints) {
     return constraints.constrain(desiredSize);
   }
 
   void performLayout() {
     size = constraints.constrain(desiredSize);
   }
 
   void handlePointer(PointerEvent event) {
     if (event.type == 'pointerdown')
       decoration = new BoxDecoration(backgroundColor: const Color(0xFFFF0000));
     else if (event.type == 'pointerup')
       decoration = new BoxDecoration(backgroundColor: backgroundColor);
   }
 }