Switch analysis_server to use 'package:test'.

pkg/analysis_server/test/analysis_server_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // 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 test.analysis_server;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/context_manager.dart';
 import 'package:analysis_server/src/domain_server.dart';
 import 'package:analysis_server/src/operation/operation.dart';
 import 'package:analysis_server/src/plugin/server_plugin.dart';
 import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/source/package_map_resolver.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:plugin/manager.dart';
 import 'package:plugin/plugin.dart';
+import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:typed_mock/typed_mock.dart';
-import 'package:unittest/unittest.dart';
 
 import 'mock_sdk.dart';
 import 'mocks.dart';
 import 'utils.dart';
 
 main() {
   initializeTestEnvironment();
-  defineReflectiveTests(AnalysisServerTest);
+  defineReflectiveSuite(() {
+    defineReflectiveTests(AnalysisServerTest);
+  });
 }
 
 @reflectiveTest
 class AnalysisServerTest {
   MockServerChannel channel;
   AnalysisServer server;
   MemoryResourceProvider resourceProvider;
   MockPackageMapProvider packageMapProvider;
 
   /**
@@ skipping 522 matching lines @@
   _MockServerOperation(this.context);
 
   @override
   ServerOperationPriority get priority => ServerOperationPriority.ANALYSIS;
 
   @override
   void perform(AnalysisServer server) {
     isComplete = true;
   }
 }