move context id constant to AnalysisServer

pkg/analysis_server/test/analysis_server_test.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 test.analysis_server;
 
 import 'dart:async';
 
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/source_io.dart';
@@ skipping 88 matching lines @@
     context.when(callsTo('performAnalysisTask')).thenReturn(
         new AnalysisResult(null, 0, null, 0));
     return pumpEventQueue().then((_) =>
         context.getLogs(callsTo('performAnalysisTask')).verify(happenedExactly(1)));
   }
 
   static Future createContext() {
     server.handlers = [new ServerDomainHandler(server)];
     var request = new Request('my27', ServerDomainHandler.CREATE_CONTEXT_METHOD);
     request.setParameter(ServerDomainHandler.SDK_DIRECTORY_PARAM, sdkPath);
-    request.setParameter(ServerDomainHandler.CONTEXT_ID_PARAM, 'ctx');
+    request.setParameter(AnalysisServer.CONTEXT_ID_PARAM, 'ctx');
     return channel.sendRequest(request)
         .then((Response response) {
           expect(response.id, equals('my27'));
           expect(response.error, isNull);
         });
   }
 
   static Future echo() {
     server.handlers = [new EchoHandler()];
     var request = new Request('my22', 'echo');
@@ skipping 86 matching lines @@
   @override
   Response handleRequest(Request request) {
     if (request.method == 'echo') {
       var response = new Response(request.id);
       response.setResult('echo', true);
       return response;
     }
     return null;
   }
 }