Add zone task support for request-anim.

sdk/lib/html/dartium/html_dartium.dart

Index: sdk/lib/html/dartium/html_dartium.dart
diff --git a/sdk/lib/html/dartium/html_dartium.dart b/sdk/lib/html/dartium/html_dartium.dart
index 26fc739abe27c89b3e3d6c1eafcdde3ba3454f36..b3300761e306a1a597d3485c127108009570c54c 100644
--- a/sdk/lib/html/dartium/html_dartium.dart
+++ b/sdk/lib/html/dartium/html_dartium.dart
@@ -39131,6 +39131,77 @@ class WheelEvent extends MouseEvent {
 // BSD-style license that can be found in the LICENSE file.
 
 
+typedef void RemoveFrameRequestMapping(int id);
+
+/**
+ * The task object representing animation-frame requests.
+ *
+ * For historical reasons, [Window.requestAnimationFrame] returns an integer
+ * to users. However, zone-tasks must be unique objects, and an integer thus
+ * doesn't work. The [Window] class thus keeps a mapping from the id to the
+ * corresponding task object. All zone related operations work on this task
+ * object, whereas users of [Window.requestAnimationFrame] only see the integer
+ * id.
+ *
+ * Since this mapping takes space, it must be removed as soon as the animation-
+ * frame task triggered. The default-implementations do this automatically, but
+ * intercepted implementations of `requestAnimationFrame` must ensure to
+ * call the [AnimationFrameRequestSpecification.removeMapping] function that is
+ * provided in the task specification.
+ */
+abstract class AnimationFrameTask {
+  /** The id that is returned to users. */
+  int get id;
+
+  /** The function that is invoked when the user cancels the request. */
+  void cancel(Window window);
+
+  /** The zone in which the task should run (and cancel). */
+  Zone get zone;
+}
+
+class _AnimationFrameTask implements AnimationFrameTask {
+  final int id;
+  final Zone zone;
+  final FrameRequestCallback _callback;
+
+  _AnimationFrameTask(this.id, this.zone, this._callback);
+
+  void cancel(Window window) {
+    window._cancelAnimationFrame(this.id);
+  }
+}
+
+/**
+ * The task specification for an animation-frame request.
+ *
+ * The task specification of animation-frame requests include a `removeMapping`
+ * function. This function must be called by the created task before it
+ * runs the frame-request callback.
+ */
+class AnimationFrameRequestSpecification implements TaskSpecification {
+  final Window window;
+  /**
+   * The callback that should be executed when the animation-frame is ready.
+   *
+   * Note that the callback hasn't been registered in any zone yet.
+   */
+  final FrameRequestCallback callback;
+
+  /**
+   * The function that should be invoked by the task before running [callback].
+   *
+   * See [AnimationFrame].
+   */
+  final RemoveFrameRequestMapping removeMapping;
+
+  AnimationFrameRequestSpecification(
+      this.window, this.callback, this.removeMapping);
+
+  String get name => "dart.html.request-animation-frame";
+  bool get isOneShot => true;
+}
+
 @DocsEditable()
 /**
  * Top-level container for the current browser tab or window.
@@ -39185,9 +39256,7 @@ class Window extends EventTarget implements WindowEventHandlers, WindowBase, Glo
    */
   Future<num> get animationFrame {
     var completer = new Completer<num>.sync();
-    requestAnimationFrame((time) {
-      completer.complete(time);
-    });
+    requestAnimationFrame(completer.complete);
     return completer.future;
   }