Clean up stock_app.dart

sky/framework/components/drawer.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 'animated_component.dart';
 import '../animation/animated_value.dart';
 import '../animation/curves.dart';
 import '../fn.dart';
 import '../theme/colors.dart';
 import '../theme/shadows.dart';
 import 'dart:async';
 import 'dart:math' as math;
 import 'dart:sky' as sky;
 import 'material.dart';
 
 const double _kWidth = 304.0;
 const double _kMinFlingVelocity = 0.4;
 const double _kBaseSettleDurationMS = 246.0;
 const double _kMaxSettleDurationMS = 600.0;
 const Curve _kAnimationCurve = parabolicRise;
 
 class DrawerController {
   final AnimatedValue position = new AnimatedValue(-_kWidth);
 
+  bool get isClosed => position.value == -_kWidth;
+
   bool get _isMostlyClosed => position.value <= -_kWidth / 2;
 
   void toggle(_) => _isMostlyClosed ? _open() : _close();
 
   void handleMaskTap(_) => _close();
 
   void handlePointerDown(_) => position.stop();
 
   void handlePointerMove(sky.PointerEvent event) {
     if (position.isAnimating)
@@ skipping 111 matching lines @@
         inlineStyle: inlineStyle,
         children: [ mask, content ]
       ),
       onPointerDown: controller.handlePointerDown,
       onPointerMove: controller.handlePointerMove,
       onPointerUp: controller.handlePointerUp,
       onPointerCancel: controller.handlePointerCancel
     );
   }
 }