As a temporary measure, allow SDK to be specified on analysis server cmd line.

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 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/domain_server.dart';
 import 'package:analysis_server/src/operation/operation.dart';
 import 'package:analysis_server/src/protocol.dart';
+import 'package:analysis_testing/mock_sdk.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:mock/mock.dart';
 import 'package:unittest/unittest.dart';
 
 import 'mocks.dart';
 
 main() {
   group('AnalysisServer', () {
@@ skipping 80 matching lines @@
   });
 }
 
 class AnalysisServerTestHelper {
   MockServerChannel channel;
   AnalysisServer server;
 
   AnalysisServerTestHelper({bool rethrowExceptions: true}) {
     channel = new MockServerChannel();
     server = new AnalysisServer(channel, PhysicalResourceProvider.INSTANCE,
-        new MockPackageMapProvider(), null,
+        new MockPackageMapProvider(), null, new MockSdk(),
         rethrowExceptions: rethrowExceptions);
   }
 }
 
 class EchoHandler implements RequestHandler {
   @override
   Response handleRequest(Request request) {
     if (request.method == 'echo') {
       var response = new Response(request.id);
       response.setResult('echo', true);
       return response;
     }
     return null;
   }
 }