Move client/{base, observable, layout, touch, util, view} to samples/ui_lib .

client/base/Env.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.
-
-/**
- * This class has static fields that hold objects that this isolate
- * uses to interact with the environment.  Which objects are available
- * depend on how the isolate was started.  In the UI isolate
- * of the browser, the window object is available.
- */
-class Env {
-  static AnimationScheduler _animationScheduler;
-
-  /**
-   * Provides functionality similar to [:window.requestAnimationFrame:] for
-   * all platforms. [callback] is executed on the next animation frame that
-   * occurs at or after [minTime].  If [minTime] is not specified, the first
-   * available animation frame is used.  Returns an id that can be used to
-   * cancel the pending callback.
-   */
-  static int requestAnimationFrame(AnimationCallback callback,
-                                   [Element element = null,
-                                    num minTime = null]) {
-    if (_animationScheduler == null) {
-      _animationScheduler = new AnimationScheduler();
-    }
-    return _animationScheduler.requestAnimationFrame(
-        callback, element, minTime);
-  }
-
-  /**
-   * Cancel the pending callback callback matching the specified [id].
-   */
-  static void cancelRequestAnimationFrame(int id) {
-    window.clearTimeout(id);
-    _animationScheduler.cancelRequestAnimationFrame(id);
-  }
-}
-
-typedef void XMLHttpRequestCompleted(XMLHttpRequest req);