Switch analysis_server to use 'package:test'.

pkg/analysis_server/test/domain_analysis_test.dart

Index: pkg/analysis_server/test/domain_analysis_test.dart
diff --git a/pkg/analysis_server/test/domain_analysis_test.dart b/pkg/analysis_server/test/domain_analysis_test.dart
index 485227d9a89bcc401b74a0046a62a20d5411e328..f710c611e6133c4d27c4d3f5dd4d00eddbd509e4 100644
--- a/pkg/analysis_server/test/domain_analysis_test.dart
+++ b/pkg/analysis_server/test/domain_analysis_test.dart
@@ -15,8 +15,8 @@ import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:plugin/manager.dart';
+import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
-import 'package:unittest/unittest.dart';
 
 import 'analysis_abstract.dart';
 import 'mock_sdk.dart';
@@ -26,8 +26,10 @@ import 'utils.dart';
 main() {
   initializeTestEnvironment();
 
-  defineReflectiveTests(AnalysisDomainTest);
-  defineReflectiveTests(SetSubscriptionsTest);
+  defineReflectiveSuite(() {
+    defineReflectiveTests(AnalysisDomainTest);
+    defineReflectiveTests(SetSubscriptionsTest);
+  });
 
   MockServerChannel serverChannel;
   MemoryResourceProvider resourceProvider;