Rename Error to RequestError in analysis server API.

pkg/analysis_server/lib/src/socket_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 socket.server;
 
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/channel.dart';
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analysis_server/src/domain_completion.dart';
@@ skipping 34 matching lines @@
   final DirectoryBasedDartSdk defaultSdk;
 
   SocketServer(this.defaultSdk);
 
   /**
    * Create an analysis server which will communicate with the client using the
    * given serverChannel.
    */
   void createAnalysisServer(ServerCommunicationChannel serverChannel) {
     if (analysisServer != null) {
-      RequestError error = new RequestError.serverAlreadyStarted();
+      RequestError error = new RequestError(
+          RequestErrorCode.SERVER_ALREADY_STARTED, "Server already started");
       serverChannel.sendResponse(new Response('', error: error));
       serverChannel.listen((Request request) {
         serverChannel.sendResponse(new Response(request.id, error: error));
       });
       return;
     }
     PhysicalResourceProvider resourceProvider = PhysicalResourceProvider.INSTANCE;
     analysisServer = new AnalysisServer(
         serverChannel,
         resourceProvider,
@@ skipping 10 matching lines @@
   void _initializeHandlers(AnalysisServer server) {
     server.handlers = [
         new ServerDomainHandler(server),
         new AnalysisDomainHandler(server),
         new EditDomainHandler(server),
         new SearchDomainHandler(server),
         new CompletionDomainHandler(server),
     ];
   }
 }