Generate constants in server as we do in plugin

pkg/analysis_server/test/analysis/notification_implemented_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.
 
 import 'dart:async';
 
 import 'package:analysis_server/protocol/protocol.dart';
+import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
-import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/services/index/index.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../analysis_abstract.dart';
 
 main() {
   defineReflectiveSuite(() {
     defineReflectiveTests(AnalysisNotificationImplementedTest);
@@ skipping 80 matching lines @@
 
   /**
    * Subscribe for `IMPLEMENTED` and wait for the notification.
    */
   Future prepareImplementedElements() {
     subscribeForImplemented();
     return waitForImplementedElements();
   }
 
   void processNotification(Notification notification) {
-    if (notification.event == ANALYSIS_IMPLEMENTED) {
+    if (notification.event == ANALYSIS_NOTIFICATION_IMPLEMENTED) {
       var params = new AnalysisImplementedParams.fromNotification(notification);
       if (params.file == testFile) {
         implementedClasses = params.classes;
         implementedMembers = params.members;
       }
     }
   }
 
   void setUp() {
     super.setUp();
@@ skipping 308 matching lines @@
       if (times == 0 || implementedClasses != null) {
         return new Future.value();
       }
       return new Future.delayed(
           new Duration(milliseconds: 1), () => waitForNotification(times - 1));
     }
 
     return waitForNotification(30000);
   }
 }