Rename all the things

sky/sdk/lib/framework/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);
-}
-
-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;
-}