Switch analysis_server to use 'package:test'.

pkg/analysis_server/test/analysis/set_priority_files_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.set_priority_files;
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analyzer/src/generated/engine.dart'
     show InternalAnalysisContext;
 import 'package:analyzer/src/generated/source.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 '../mocks.dart';
 import '../utils.dart';
 
 main() {
   initializeTestEnvironment();
-  defineReflectiveTests(SetPriorityFilesTest);
+  defineReflectiveSuite(() {
+    defineReflectiveTests(SetPriorityFilesTest);
+  });
 }
 
 @reflectiveTest
 class SetPriorityFilesTest extends AbstractAnalysisTest {
   @override
   void setUp() {
     super.setUp();
-    server.handlers = [new AnalysisDomainHandler(server),];
+    server.handlers = [
+      new AnalysisDomainHandler(server),
+    ];
     createProject();
   }
 
   test_fileDoesNotExist() async {
     String file = '$projectPath/doesNotExist.dart';
     Response response = await _setPriorityFile(file);
     expect(response, isResponseSuccess('0'));
   }
 
   test_fileInAnalysisRoot() async {
@@ skipping 83 matching lines @@
     expect(response.error, isNotNull);
     expect(response.error.code, RequestErrorCode.UNANALYZED_PRIORITY_FILES);
   }
 
   _setPriorityFile(String file) async {
     Request request =
         new AnalysisSetPriorityFilesParams(<String>[file]).toRequest('0');
     return await serverChannel.sendRequest(request);
   }
 }