Replace setBoxDecoration() with a decoration property. (part II)

sky/examples/raw/sector-layout.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:math' as math;
 import 'dart:sky' as sky;
 import 'package:sky/framework/app.dart';
 import 'package:sky/framework/layout2.dart';
 
 const double kTwoPi = 2 * math.PI;
@@ skipping 80 matching lines @@
 
   double deltaRadius;
   double deltaTheta;
 }
 
 class RenderDecoratedSector extends RenderSector {
   BoxDecoration _decoration;
 
   RenderDecoratedSector(BoxDecoration decoration) : _decoration = decoration;
 
-  void setBoxDecoration(BoxDecoration decoration) {
-    if (_decoration == decoration)
+  BoxDecoration _decoration;
+  BoxDecoration get decoration => _decoration;
+  void set decoration (BoxDecoration value) {
+    if (value == _decoration)
       return;
-    _decoration = decoration;
+    _decoration = value;
     markNeedsPaint();
   }
 
   // origin must be set to the center of the circle
   void paint(RenderNodeDisplayList canvas) {
     assert(deltaRadius != null);
     assert(deltaTheta != null);
     assert(parentData is SectorParentData);
 
     if (_decoration == null)
@@ skipping 410 matching lines @@
   rootCircle.add(new RenderSolidColor(0xFF0000FF, desiredDeltaTheta: kTwoPi * 0.4));
   var stack = new RenderSectorSlice(padding: 2.0);
   stack.add(new RenderSolidColor(0xFFFFFF00, desiredDeltaRadius: 20.0));
   stack.add(new RenderSolidColor(0xFFFF9000, desiredDeltaRadius: 20.0));
   stack.add(new RenderSolidColor(0xFF00FF00));
   rootCircle.add(stack);
 
   var root = new RenderBoxToRenderSectorAdapter(innerRadius: 50.0, child: rootCircle);
   app = new AppView(root);
 }