Migrate the samples to one-argument version of requestAnimationFrame and re-enable the test.

samples/spirodraw/Spirodraw.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.
 
 #library('spirodraw');
 
 #import('dart:html');
 #source("ColorPicker.dart");
 // TODO(732): Reenable when this works in the VM.
 // #resource("spirodraw.css");
@@ skipping 146 matching lines @@
     }
     drawWheel(theta);
   }
 
   void animate(int time) {
     if (run && rad <= maxTurns * PI2) {
       rad+=stepSize;
       drawFrame(rad);
       int nTurns = (rad / PI2).toInt();
       numTurns.text = '${nTurns}/$maxTurns';
-      window.webkitRequestAnimationFrame(animate, frontCanvas);
+      window.webkitRequestAnimationFrame(animate);
     } else {
       stop();
     }
   }
   
   void start() {
     refresh();
     rad = 0.0;
     run = true;
-    window.webkitRequestAnimationFrame(animate, frontCanvas); 
+    window.webkitRequestAnimationFrame(animate);
   }
 
   int calcTurns() {
     // compute ratio of wheel radius to big R then find LCM
     if ((dUnits==0) || (rUnits==0))
       return 1;
     int ru = rUnits.abs();
     int wrUnits = RUnits + rUnits;
     int g = gcf (wrUnits, ru);
     return (ru ~/ g).toInt();
@@ skipping 113 matching lines @@
 
 int gcf(int n, int d) {
   if (n==d)
     return n;
   int max = Math.max(n, d);
   for (int i = max ~/ 2; i > 1; i--)
     if ((n % i == 0) && (d % i == 0))
       return i;
   return 1;
 }