Check for compile-time constants in DartCompiler

client/samples/spirodraw/ColorPicker.dart

 // Copyright (c) 2011, 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.
 
 typedef void PickerListener(String selectedColor);
 
 class ColorPicker {
 
-  static final hexValues = ['00', '33', '66', '99', 'CC', 'FF'];
+  static final hexValues = const ['00', '33', '66', '99', 'CC', 'FF'];
   static final COLS = 18;
   // Block height, width, padding
   static final BH = 10;
   static final BW = 10;
   static final BP = 1;
   final List<PickerListener> _listeners;
   HTMLCanvasElement canvasElement;
   String _selectedColor = 'red';
   final height = 160;
   final width = 180;
@@ skipping 84 matching lines @@
   }
   
   String getHexString(int i) {
     int r = i ~/ 36;
     int g = (i % 36) ~/ 6;
     int b = i % 6;
     return '#${hexValues[r]}${hexValues[g]}${hexValues[b]}';
   }
   
 }