Generate constants in server as we do in plugin

pkg/analysis_server/lib/src/domain_analytics.dart

 // Copyright (c) 2017, 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:core';
 
 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/analysis_server.dart';
-import 'package:analysis_server/src/constants.dart';
 
 /// Instances of the class [AnalyticsDomainHandler] implement a [RequestHandler]
 /// that handles requests in the `analytics` domain.
 class AnalyticsDomainHandler implements RequestHandler {
   final AnalysisServer server;
 
   bool enabled = false;
 
   AnalyticsDomainHandler(this.server);
 
   // TODO(devoncarew): This implementation is currently mocked out.
   Response handleEnable(Request request) {
     // TODO(devoncarew): Implement.
     AnalyticsEnableParams params =
         new AnalyticsEnableParams.fromRequest(request);
     enabled = params.value;
     return new AnalyticsEnableResult().toResponse(request.id);
   }
 
   Response handleIsEnabled(Request request) {
     // TODO(devoncarew): Implement.
     return new AnalyticsIsEnabledResult(enabled).toResponse(request.id);
   }
 
   @override
   Response handleRequest(Request request) {
     String requestName = request.method;
-    if (requestName == ANALYTICS_IS_ENABLED) {
+    if (requestName == ANALYTICS_REQUEST_IS_ENABLED) {
       return handleIsEnabled(request);
-    } else if (requestName == ANALYTICS_ENABLE) {
+    } else if (requestName == ANALYTICS_REQUEST_ENABLE) {
       return handleEnable(request);
-    } else if (requestName == ANALYTICS_SEND_EVENT) {
+    } else if (requestName == ANALYTICS_REQUEST_SEND_EVENT) {
       return handleSendEvent(request);
-    } else if (requestName == ANALYTICS_SEND_TIMING) {
+    } else if (requestName == ANALYTICS_REQUEST_SEND_TIMING) {
       return handleSendTiming(request);
     }
 
     return null;
   }
 
   Response handleSendEvent(Request request) {
     // TODO(devoncarew): Implement.
     return new AnalyticsSendEventResult().toResponse(request.id);
   }
 
   Response handleSendTiming(Request request) {
     // TODO(devoncarew): Implement.
     return new AnalyticsSendTimingResult().toResponse(request.id);
   }
 }