Use package:test_reflective_loader instead of reflective_tests.

pkg/analysis_server/test/edit/assists_test.dart

Index: pkg/analysis_server/test/edit/assists_test.dart
diff --git a/pkg/analysis_server/test/edit/assists_test.dart b/pkg/analysis_server/test/edit/assists_test.dart
index fd5f71785cd69b41d12c23b306cfce665bb07506..ebe243084c3ae4c5be53d19cbf731cb4d5473670 100644
--- a/pkg/analysis_server/test/edit/assists_test.dart
+++ b/pkg/analysis_server/test/edit/assists_test.dart
@@ -10,14 +10,14 @@ import 'package:analysis_server/src/edit/edit_domain.dart';
 import 'package:analysis_server/src/plugin/server_plugin.dart';
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analyzer/src/plugin/plugin_impl.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:unittest/unittest.dart' hide ERROR;
 
 import '../analysis_abstract.dart';
-import '../reflective_tests.dart';
 
 main() {
   groupSep = ' | ';
-  runReflectiveTests(AssistsTest);
+  defineReflectiveTests(AssistsTest);
 }
 
 @reflectiveTest