Deploy TaskDescription to the rest of our demos

sky/sdk/example/rendering/interactive_flex.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 'dart:math' as math;
 
 import 'package:sky/mojo/activity.dart' as activity;
 import 'package:sky/mojo/net/image_cache.dart' as image_cache;
 import 'package:sky/painting/text_style.dart';
@@ skipping 57 matching lines @@
   image_cache.load("https://www.dartlang.org/logos/dart-logo.png").then((Image dartLogo) {
     image.image = dartLogo;
   });
 
   var padding = new RenderPadding(padding: const EdgeDims.all(10.0), child: image);
   row.add(padding);
 
   RenderFlex column = new RenderFlex(direction: FlexDirection.vertical);
 
   // Top cell
-  addFlexChildSolidColor(column, const Color(0xFF55DDCA), flex: 1);
+  final Color topColor = const Color(0xFF55DDCA);
+  addFlexChildSolidColor(column, topColor, flex: 1);
 
   // The internet is a beautiful place.  https://baconipsum.com/
   String meatyString = """Bacon ipsum dolor amet ham fatback tri-tip, prosciutto
 porchetta bacon kevin meatball meatloaf pig beef ribs chicken. Brisket ribeye
 andouille leberkas capicola meatloaf. Chicken pig ball tip pork picanha bresaola
 alcatra. Pork pork belly alcatra, flank chuck drumstick biltong doner jowl.
 Pancetta meatball tongue tenderloin rump tail jowl boudin.""";
   var text = new InlineStyle(
       new TextStyle(color:  const Color(0xFF009900)),
       [new InlineText(meatyString)]);
   padding = new RenderPadding(
       padding: const EdgeDims.all(10.0),
       child: new RenderParagraph(text));
   column.add(padding);
 
   // Bottom cell
   addFlexChildSolidColor(column, const Color(0xFF0081C6), flex: 2);
 
   row.add(column);
   column.parentData.flex = 8;
 
   RenderDecoratedBox root = new RenderDecoratedBox(
     decoration: new BoxDecoration(backgroundColor: const Color(0xFFFFFFFF)),
     child: row
   );
 
+  activity.updateTaskDescription('Interactive Flex', topColor);
   new SkyBinding(root: root);
   view.setEventCallback(handleEvent);
 }