Switch analysis_server to use 'package:test'.

pkg/analysis_server/test/analysis/reanalyze_test.dart

Index: pkg/analysis_server/test/analysis/reanalyze_test.dart
diff --git a/pkg/analysis_server/test/analysis/reanalyze_test.dart b/pkg/analysis_server/test/analysis/reanalyze_test.dart
index b7f62d05e555d2a27657926d9a4949c27c741f7a..464509a1fa0fea8a1d971462aa4bfb6bed2b9223 100644
--- a/pkg/analysis_server/test/analysis/reanalyze_test.dart
+++ b/pkg/analysis_server/test/analysis/reanalyze_test.dart
@@ -7,15 +7,17 @@ library test.analysis.reanalyze;
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analyzer/src/generated/engine.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 '../utils.dart';
 
 main() {
   initializeTestEnvironment();
-  defineReflectiveTests(ReanalyzeTest);
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ReanalyzeTest);
+  });
 }
 
 @reflectiveTest