Rename scheduleFrame/setBeginFrameCallback

sky/sdk/lib/base/scheduler.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:sky' as sky;
 
 typedef void Callback(double timeStamp);
 
 bool _haveScheduledVisualUpdate = false;
 int _nextCallbackId = 1;
 
 final List<Callback> _persistentCallbacks = new List<Callback>();
 Map<int, Callback> _transientCallbacks = new Map<int, Callback>();
 
 void _beginFrame(double timeStamp) {
   _haveScheduledVisualUpdate = false;
 
   Map<int, Callback> callbacks = _transientCallbacks;
   _transientCallbacks = new Map<int, Callback>();
 
   callbacks.forEach((id, callback) {
     callback(timeStamp);
   });
 
   for (Callback callback in _persistentCallbacks)
     callback(timeStamp);
 }
 
 void init() {
-  assert(sky.window == null);
-  sky.view.setBeginFrameCallback(_beginFrame);
+  sky.view.setFrameCallback(_beginFrame);
 }
 
 void addPersistentFrameCallback(Callback callback) {
-  assert(sky.window == null);
   _persistentCallbacks.add(callback);
 }
 
 int requestAnimationFrame(Callback callback) {
-  if (sky.window != null)
-    return sky.window.requestAnimationFrame(callback);
   int id = _nextCallbackId++;
   _transientCallbacks[id] = callback;
   ensureVisualUpdate();
   return id;
 }
 
 void cancelAnimationFrame(int id) {
-  if (sky.window != null)
-    return sky.window.cancelAnimationFrame(id);
   _transientCallbacks.remove(id);
 }
 
 void ensureVisualUpdate() {
-  assert(sky.window == null);
   if (_haveScheduledVisualUpdate)
     return;
   sky.view.scheduleFrame();
   _haveScheduledVisualUpdate = true;
 }