Remove workaround

test/codegen/sunflower/sunflower.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library sunflower;
 
 import 'dart:math';
 import 'dom.dart';
 
 const ORANGE = "orange";
 const SEED_RADIUS = 2;
 const SCALE_FACTOR = 4;
 const TAU = PI * 2;
 const MAX_D = 300;
-// TODO(sigmund): remove `num` here, this is to workaround dartbug.com/22937
-const num centerX = MAX_D / 2;
-const num centerY = centerX;
+const centerX = MAX_D / 2;
+const centerY = centerX;
 
 Element querySelector(String selector) => document.querySelector(selector);
 
 final InputElement slider = querySelector("#slider");
 final notes = querySelector("#notes");
 final PHI = (sqrt(5) + 1) / 2;
 int seeds = 0;
 final CanvasRenderingContext2D context =
     (querySelector("#canvas") as CanvasElement).getContext('2d');
 
@@ skipping 40 matching lines @@
       ..closePath()
       ..stroke();
   }
 }
 
 class Circle {
   final num x, y, radius;
 
   Circle(this.x, this.y, this.radius);
 }