Generate constants in server as we do in plugin

pkg/analysis_server/lib/src/edit/edit_domain.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/plugin/edit/assist/assist_core.dart';
 import 'package:analysis_server/plugin/edit/assist/assist_dart.dart';
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
 import 'package:analysis_server/plugin/edit/fix/fix_dart.dart';
+import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/collections.dart';
-import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/domain_abstract.dart';
 import 'package:analysis_server/src/plugin/plugin_manager.dart';
 import 'package:analysis_server/src/plugin/result_converter.dart';
 import 'package:analysis_server/src/protocol_server.dart' hide Element;
 import 'package:analysis_server/src/services/completion/postfix/postfix_completion.dart';
 import 'package:analysis_server/src/services/completion/statement/statement_completion.dart';
 import 'package:analysis_server/src/services/correction/assist_internal.dart';
 import 'package:analysis_server/src/services/correction/fix_internal.dart';
 import 'package:analysis_server/src/services/correction/organize_directives.dart';
 import 'package:analysis_server/src/services/correction/sort_members.dart';
@@ skipping 307 matching lines @@
 
     Response response = new EditGetStatementCompletionResult(change, false)
         .toResponse(request.id);
     server.sendResponse(response);
   }
 
   @override
   Response handleRequest(Request request) {
     try {
       String requestName = request.method;
-      if (requestName == EDIT_FORMAT) {
+      if (requestName == EDIT_REQUEST_FORMAT) {
         return format(request);
-      } else if (requestName == EDIT_GET_ASSISTS) {
+      } else if (requestName == EDIT_REQUEST_GET_ASSISTS) {
         getAssists(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_GET_AVAILABLE_REFACTORINGS) {
+      } else if (requestName == EDIT_REQUEST_GET_AVAILABLE_REFACTORINGS) {
         return _getAvailableRefactorings(request);
-      } else if (requestName == EDIT_GET_FIXES) {
+      } else if (requestName == EDIT_REQUEST_GET_FIXES) {
         getFixes(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_GET_REFACTORING) {
+      } else if (requestName == EDIT_REQUEST_GET_REFACTORING) {
         return _getRefactoring(request);
-      } else if (requestName == EDIT_ORGANIZE_DIRECTIVES) {
+      } else if (requestName == EDIT_REQUEST_ORGANIZE_DIRECTIVES) {
         organizeDirectives(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_SORT_MEMBERS) {
+      } else if (requestName == EDIT_REQUEST_SORT_MEMBERS) {
         sortMembers(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_GET_STATEMENT_COMPLETION) {
+      } else if (requestName == EDIT_REQUEST_GET_STATEMENT_COMPLETION) {
         getStatementCompletion(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_IS_POSTFIX_COMPLETION_APPLICABLE) {
+      } else if (requestName == EDIT_REQUEST_IS_POSTFIX_COMPLETION_APPLICABLE) {
         isPostfixCompletionApplicable(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_GET_POSTFIX_COMPLETION) {
+      } else if (requestName == EDIT_REQUEST_GET_POSTFIX_COMPLETION) {
         getPostfixCompletion(request);
         return Response.DELAYED_RESPONSE;
-      } else if (requestName == EDIT_LIST_POSTFIX_COMPLETION_TEMPLATES) {
+      } else if (requestName ==
+          EDIT_REQUEST_LIST_POSTFIX_COMPLETION_TEMPLATES) {
         listPostfixCompletionTemplates(request);
         return Response.DELAYED_RESPONSE;
       }
     } on RequestFailure catch (exception) {
       return exception.response;
     }
     return null;
   }
 
   Future isPostfixCompletionApplicable(Request request) async {
@@ skipping 643 matching lines @@
     }
     return new RefactoringStatus();
   }
 }
 
 /**
  * [_RefactoringManager] throws instances of this class internally to stop
  * processing in a manager that was reset.
  */
 class _ResetError {}