Use Timer and not AnimationFrame during Observatory UI tests

runtime/observatory/tests/observatory_ui/nav/refresh/element_test.dart

Index: runtime/observatory/tests/observatory_ui/nav/refresh/element_test.dart
diff --git a/runtime/observatory/tests/observatory_ui/nav/refresh/element_test.dart b/runtime/observatory/tests/observatory_ui/nav/refresh/element_test.dart
index 26c3adaaa4c47a779d23dc4abb43eec5fba29ad1..2154ba977f4121059c934691fbffdc861aface7a 100644
--- a/runtime/observatory/tests/observatory_ui/nav/refresh/element_test.dart
+++ b/runtime/observatory/tests/observatory_ui/nav/refresh/element_test.dart
@@ -4,10 +4,14 @@
 import 'dart:html';
 import 'dart:async';
 import 'package:unittest/unittest.dart';
+import 'package:observatory/src/elements/helpers/rendering_queue.dart';
 import 'package:observatory/src/elements/nav/refresh.dart';
 
 main() {
   NavRefreshElement.tag.ensureRegistration();
+
+  final TimedRenderingBarrier barrier = new TimedRenderingBarrier();
+  final RenderingQueue queue = new RenderingQueue.fromBarrier(barrier);
   group('instantiation', () {
     test('no parameters', () {
       final NavRefreshElement e = new NavRefreshElement();
@@ -35,7 +39,7 @@ main() {
   });
   group('elements', () {
     test('created after attachment', () async {
-      final NavRefreshElement e = new NavRefreshElement();
+      final NavRefreshElement e = new NavRefreshElement(queue: queue);
       document.body.append(e);
       await e.onRendered.first;
       expect(e.children.length, isNonZero, reason: 'has elements');
@@ -45,7 +49,8 @@ main() {
     });
     test('contain custom label', () async {
       final label = 'custom-label';
-      final NavRefreshElement e = new NavRefreshElement(label: label);
+      final NavRefreshElement e = new NavRefreshElement(label: label,
+          queue: queue);
       document.body.append(e);
       await e.onRendered.first;
       expect(e.innerHtml.contains(label), isTrue);
@@ -55,7 +60,8 @@ main() {
     test('react to label change', () async {
       final label1 = 'custom-label-1';
       final label2 = 'custom-label-2';
-      final NavRefreshElement e = new NavRefreshElement(label: label1);
+      final NavRefreshElement e = new NavRefreshElement(label: label1,
+          queue: queue);
       document.body.append(e);
       await e.onRendered.first;
       expect(e.innerHtml.contains(label1), isTrue);
@@ -68,7 +74,8 @@ main() {
       await e.onRendered.first;
     });
     test('react to disabled change', () async {
-      final NavRefreshElement e = new NavRefreshElement(disabled: false);
+      final NavRefreshElement e = new NavRefreshElement(disabled: false,
+          queue: queue);
       document.body.append(e);
       await e.onRendered.first;
       expect(e.disabled, isFalse);
@@ -83,7 +90,7 @@ main() {
     NavRefreshElement e;
     StreamSubscription sub;
     setUp(() async {
-      e = new NavRefreshElement();
+      e = new NavRefreshElement(queue: queue);
       document.body.append(e);
       await e.onRendered.first;
     });