Add ServerOperation and queue.

pkg/analysis_server/test/operation/operation_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 smoke.test.mirrors_test;
+library test.operation;
 
-import 'package:smoke/mirrors.dart';
+import 'package:analysis_server/src/operation/operation.dart';
 import 'package:unittest/unittest.dart';
-import 'common.dart' as common show main;
 
 main() {
-  setUp(useMirrors);
-  common.main();
+  groupSep = ' | ';
+
+  group('ServerOperationPriority', () {
+    test('toString', () {
+      expect(ServerOperationPriority.SEARCH.toString(), 'SEARCH');
+    });
+  });
 }