[web] improve requestanimationframe test.

This test is flaky and causes timeouts 70% of the time in DDC.

The reasons are not clear at the moment, but I noticed that the
test was not properly using async-helper. This change may help
improve our investigation in the near future.

Change-Id: I834265dd6b898098ee7d5210ffe68ef0a6db74a0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/332280
Reviewed-by: Srujan Gaddam <srujzs@google.com>
Commit-Queue: Sigmund Cherem <sigmund@google.com>
diff --git a/tests/lib/html/request_animation_frame_test.dart b/tests/lib/html/request_animation_frame_test.dart
index d0c0447..4e330d9 100644
--- a/tests/lib/html/request_animation_frame_test.dart
+++ b/tests/lib/html/request_animation_frame_test.dart
@@ -7,7 +7,8 @@
 import 'dart:async';
 import 'dart:html';
 
-import 'package:expect/minitest.dart';
+import 'package:async_helper/async_helper.dart';
+import 'package:expect/expect.dart';
 
 Future testOneShot() async {
   final done = new Completer();
@@ -34,9 +35,9 @@
 Future testCancel1() async {
   final done = new Completer();
   var frame1 = window.requestAnimationFrame((timestamp1) {
-    fail('Should have been cancelled');
+    Expect.fail('Should have been cancelled');
   });
-  var frame2 = window.requestAnimationFrame(done.complete);
+  window.requestAnimationFrame(done.complete);
   window.cancelAnimationFrame(frame1);
   await done.future;
 }
@@ -44,18 +45,20 @@
 Future testCancel2() async {
   final done1 = new Completer();
   final done2 = new Completer();
-  var frame1 = window.requestAnimationFrame(done1.complete);
+  window.requestAnimationFrame(done1.complete);
   var frame2 = window.requestAnimationFrame((timestamp2) {
-    fail('Should have been cancelled');
+    Expect.fail('Should have been cancelled');
   });
-  var frame3 = window.requestAnimationFrame(done2.complete);
+  window.requestAnimationFrame(done2.complete);
   window.cancelAnimationFrame(frame2);
   await Future.wait([done1.future, done2.future]);
 }
 
-main() async {
-  await testOneShot();
-  await testTwoShot();
-  await testCancel1();
-  await testCancel2();
+main() {
+  asyncTest(() async {
+    await testOneShot();
+    await testTwoShot();
+    await testCancel1();
+    await testCancel2();
+  });
 }
diff --git a/tests/lib_2/html/request_animation_frame_test.dart b/tests/lib_2/html/request_animation_frame_test.dart
index fc6f6e9..ccde046 100644
--- a/tests/lib_2/html/request_animation_frame_test.dart
+++ b/tests/lib_2/html/request_animation_frame_test.dart
@@ -9,7 +9,8 @@
 import 'dart:async';
 import 'dart:html';
 
-import 'package:expect/minitest.dart';
+import 'package:async_helper/async_helper.dart';
+import 'package:expect/expect.dart';
 
 Future testOneShot() async {
   final done = new Completer();
@@ -36,9 +37,9 @@
 Future testCancel1() async {
   final done = new Completer();
   var frame1 = window.requestAnimationFrame((timestamp1) {
-    fail('Should have been cancelled');
+    Expect.fail('Should have been cancelled');
   });
-  var frame2 = window.requestAnimationFrame(done.complete);
+  window.requestAnimationFrame(done.complete);
   window.cancelAnimationFrame(frame1);
   await done.future;
 }
@@ -46,18 +47,20 @@
 Future testCancel2() async {
   final done1 = new Completer();
   final done2 = new Completer();
-  var frame1 = window.requestAnimationFrame(done1.complete);
+  window.requestAnimationFrame(done1.complete);
   var frame2 = window.requestAnimationFrame((timestamp2) {
-    fail('Should have been cancelled');
+    Expect.fail('Should have been cancelled');
   });
-  var frame3 = window.requestAnimationFrame(done2.complete);
+  window.requestAnimationFrame(done2.complete);
   window.cancelAnimationFrame(frame2);
   await Future.wait([done1.future, done2.future]);
 }
 
-main() async {
-  await testOneShot();
-  await testTwoShot();
-  await testCancel1();
-  await testCancel2();
+main() {
+  asyncTest(() async {
+    await testOneShot();
+    await testTwoShot();
+    await testCancel1();
+    await testCancel2();
+  });
 }