Revert "Removing setImmediate and hiding WindowTimers interface"

samples/solar/web/solar.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.
 
 /**
  * A solar system visualization.
  */
 
 library solar;
 
-import 'dart:async';
 import 'dart:html';
 import 'dart:math';
 
 void main() {
   CanvasElement canvas = query("#area");
-  scheduleMicrotask(new SolarSystem(canvas).start);
+  window.setImmediate(new SolarSystem(canvas).start);
 }
 
 Element notes = query("#fps");
 num fpsAverage;
 
 /// Display the animation's FPS in a div.
 void showFps(num fps) {
   if (fpsAverage == null) fpsAverage = fps;
   fpsAverage = fps * 0.05 + fpsAverage * 0.95;
   notes.text = "${fpsAverage.round()} fps";
@@ skipping 169 matching lines @@
   num calculateSpeed(num period) =>
     period == 0.0 ? 0.0 : 1 / (60.0 * 24.0 * 2 * period);
 
   Point calculatePos(Point p) {
     if (orbitSpeed == 0.0) return p;
     num angle = solarSystem.renderTime * orbitSpeed;
     return new Point(orbitRadius * cos(angle) + p.x,
                      orbitRadius * sin(angle) + p.y);
   }
 }