Revert "Use Timer and not AnimationFrame during Observatory UI tests"

runtime/observatory/tests/observatory_ui/nav/isolate-menu/element_test.dart

Index: runtime/observatory/tests/observatory_ui/nav/isolate-menu/element_test.dart
diff --git a/runtime/observatory/tests/observatory_ui/nav/isolate-menu/element_test.dart b/runtime/observatory/tests/observatory_ui/nav/isolate-menu/element_test.dart
index 7cc0259a33922d6766bac212e49f9c470bb880c3..27bf79cac88b2e13d45e3ceb0e1aed6949b150f6 100644
--- a/runtime/observatory/tests/observatory_ui/nav/isolate-menu/element_test.dart
+++ b/runtime/observatory/tests/observatory_ui/nav/isolate-menu/element_test.dart
@@ -6,16 +6,12 @@ import 'dart:async';
 import 'package:unittest/unittest.dart';
 import 'package:observatory/models.dart';
 import 'package:observatory/mocks.dart';
-import 'package:observatory/src/elements/helpers/rendering_queue.dart';
 import 'package:observatory/src/elements/nav/menu.dart';
 import 'package:observatory/src/elements/nav/isolate_menu.dart';
 
 main(){
   NavIsolateMenuElement.tag.ensureRegistration();
 
-  final TimedRenderingBarrier barrier = new TimedRenderingBarrier();
-  final RenderingQueue queue = new RenderingQueue.fromBarrier(barrier);
-
   final String tag = NavMenuElement.tag.name;
 
   StreamController<IsolateUpdateEvent> updatesController;
@@ -40,7 +36,7 @@ main(){
   });
   test('elements created after attachment', () async {
     final NavIsolateMenuElement e = new NavIsolateMenuElement(ref,
-        updatesController.stream, queue: queue);
+                                    updatesController.stream);
     document.body.append(e);
     await e.onRendered.first;
     expect(e.shadowRoot.children.length, isNonZero, reason: 'has elements');
@@ -51,7 +47,7 @@ main(){
   group('updates', () {
     test('are correctly listen', () async {
       final NavIsolateMenuElement e = new NavIsolateMenuElement(ref,
-          updatesController.stream, queue: queue);
+                                      updatesController.stream);
       expect(updatesController.hasListener, isFalse);
       document.body.append(e);
       await e.onRendered.first;
@@ -62,7 +58,7 @@ main(){
     });
     test('have effects', () async {
       final NavIsolateMenuElement e = new NavIsolateMenuElement(ref,
-          updatesController.stream, queue: queue);
+                                      updatesController.stream);
       document.body.append(e);
       await e.onRendered.first;
       expect((e.shadowRoot.querySelector(tag) as NavMenuElement)
@@ -74,7 +70,6 @@ main(){
       expect((e.shadowRoot.querySelector(tag) as NavMenuElement)
             .label.contains(obj.name), isTrue);
       e.remove();
-      await e.onRendered.first;
     });
   });
 }