Generate constants in server as we do in plugin

pkg/analysis_server/test/analysis/update_content_test.dart

Index: pkg/analysis_server/test/analysis/update_content_test.dart
diff --git a/pkg/analysis_server/test/analysis/update_content_test.dart b/pkg/analysis_server/test/analysis/update_content_test.dart
index fdf77629af93d8679a562b062113e33a933968b6..77546a80578abaca54c808a0f44c2a7cfe75f27a 100644
--- a/pkg/analysis_server/test/analysis/update_content_test.dart
+++ b/pkg/analysis_server/test/analysis/update_content_test.dart
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 
 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/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/standard_resolution_map.dart';
@@ -41,16 +41,16 @@ class UpdateContentTest extends AbstractAnalysisTest {
 
   @override
   void processNotification(Notification notification) {
-    if (notification.event == ANALYSIS_ERRORS) {
+    if (notification.event == ANALYSIS_NOTIFICATION_ERRORS) {
       var decoded = new AnalysisErrorsParams.fromNotification(notification);
       String _format(AnalysisError e) =>
           "${e.location.startLine}: ${e.message}";
       filesErrors[decoded.file] = decoded.errors.map(_format).toList();
     }
-    if (notification.event == ANALYSIS_NAVIGATION) {
+    if (notification.event == ANALYSIS_NOTIFICATION_NAVIGATION) {
       navigationCount++;
     }
-    if (notification.event == SERVER_ERROR) {
+    if (notification.event == SERVER_NOTIFICATION_ERROR) {
       serverErrorCount++;
     }
   }