Mark analyzer_cli as strong-mode clean

pkg/analyzer_cli/test/driver_test.dart

 // Copyright (c) 2015, 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 analyzer_cli.test.driver;
 
 import 'dart:io';
 
 import 'package:analyzer/plugin/options.dart';
 import 'package:analyzer/source/analysis_options_provider.dart';
@@ skipping 500 matching lines @@
     // None
   }
 
   @override
   void registerExtensions(RegisterExtension register) {
     register(OPTIONS_PROCESSOR_EXTENSION_POINT_ID, processor);
   }
 }
 
 class TestProcessor extends OptionsProcessor {
-  Map<String, YamlNode> options;
+  Map<String, Object> options;
   Exception exception;
 
   @override
   void onError(Exception exception) {
     this.exception = exception;
   }
 
   @override
-  void optionsProcessed(
-      AnalysisContext context, Map<String, YamlNode> options) {
+  void optionsProcessed(AnalysisContext context, Map<String, Object> options) {
     this.options = options;
   }
 }
 
 class TestSource implements Source {
   TestSource();
 
   @override
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }