Reduced test case for Column height issue

column_reduced_test_case.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:async';
import 'package:sky/rendering/sky_binding.dart';
import 'package:sky/widgets.dart';
import 'package:sky/theme/colors.dart' as colors;

void main() {
  runApp(new ColumnReducedTestCase());
  new Timer(new Duration(seconds: 2), () {
    SkyBinding.instance.debugDumpRenderTree();
  });
}

class ColumnReducedTestCase extends App {

  Widget build() {
    return new Center(
      child: new Container(
        decoration: new BoxDecoration(backgroundColor: colors.white),
        child: new Block([
          new Column([
            new Container(
              margin: const EdgeDims.symmetric(vertical: 40.0),
              height: 100.0,
              width: 100.0,
              decoration: new BoxDecoration(
                backgroundColor: const Color(0x7FFF0000),
                shape: Shape.circle
              )
            )
          ])
        ])
      )
    );
  }
}