Remove uses of unittest in the HTML tests where possible.

pkg/dev_compiler/test/codegen/lib/html/notification_test.dart

Index: pkg/dev_compiler/test/codegen/lib/html/notification_test.dart
diff --git a/pkg/dev_compiler/test/codegen/lib/html/notification_test.dart b/pkg/dev_compiler/test/codegen/lib/html/notification_test.dart
index 077ea547d4cf72c7ff2aa7729e4480ef4c025db9..283dc5bce2713658f09b4e3f7ca278761b59ac49 100644
--- a/pkg/dev_compiler/test/codegen/lib/html/notification_test.dart
+++ b/pkg/dev_compiler/test/codegen/lib/html/notification_test.dart
@@ -2,15 +2,11 @@
 // 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.
 
-library notification_test;
-
-import 'package:unittest/unittest.dart';
-import 'package:unittest/html_individual_config.dart';
 import 'dart:html';
 
-main() {
-  useHtmlIndividualConfiguration();
+import 'package:expect/minitest.dart';
 
+main() {
   group('supported_notification', () {
     test('supported', () {
       expect(Notification.supported, true);