Merge two constants.dart into one.

pkg/analysis_server/lib/src/domain_server.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 domain.server;
 
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/protocol.dart';
-import 'package:analysis_server/src/services/constants.dart';
 
 /**
  * Instances of the class [ServerDomainHandler] implement a [RequestHandler]
  * that handles requests in the server domain.
  */
 class ServerDomainHandler implements RequestHandler {
   /**
    * The analysis server that is using this handler to process requests.
    */
   final AnalysisServer server;
@@ skipping 95 matching lines @@
 
   /**
    * Cleanly shutdown the analysis server.
    */
   Response shutdown(Request request) {
     server.shutdown();
     Response response = new Response(request.id);
     return response;
   }
 }