Add a TabNavigator to the Stocks demo

sky/sdk/lib/editing/editable_text.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 'dart:sky' as sky;
 
 import '../painting/text_style.dart';
 import '../rendering/object.dart';
 import '../widgets/basic.dart';
@@ skipping 49 matching lines @@
   void _stopCursorTimer() {
     _cursorTimer.cancel();
     _cursorTimer = null;
     _showCursor = false;
   }
 
   void _paintCursor(sky.Canvas canvas, Size size) {
     if (!_showCursor)
       return;
 
-    print("Draw cursor");
     Rect cursorRect =  new Rect.fromLTWH(
       _kCursorGap, 
       -_kCursorHeightOffset,
       _kCursorWidth,
       style.fontSize + 2 * _kCursorHeightOffset
     );
     canvas.drawRect(cursorRect, new Paint()..color = cursorColor);
   }
 
   Widget build() {
@@ skipping 20 matching lines @@
 
     Widget cursor = new Container(
       height: style.fontSize,
       width: _kCursorGap + _kCursorWidth,
       child: new CustomPaint(callback: _paintCursor, token: _showCursor)
     );
 
     return new Flex([text, cursor]);
   }
 }