Update a type annotation.

dart/tests/compiler/dart2js/mock_compiler.dart

 // Copyright (c) 2012, 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('mock_compiler');
 
 #import("dart:uri");
 
 #import("../../../lib/compiler/implementation/elements/elements.dart");
 #import("../../../lib/compiler/implementation/leg.dart");
@@ skipping 86 matching lines @@
   }
 
   void reportError(Node node, var message) {
     if (message is String && message.startsWith("no #library tag found in")) {
       // TODO(ahe): Fix the MockCompiler to not have this problem.
       return;
     }
     errors.add(new WarningMessage(node, message.message));
   }
 
-  void reportDiagnostic(SourceSpan span, String message, bool fatal) {
+  void reportDiagnostic(SourceSpan span, String message, var kind) {
     print(message);
   }
 
   void clearWarnings() {
     warnings = [];
   }
 
   void clearErrors() {
     errors = [];
   }
@@ skipping 82 matching lines @@
   importLibrary(library, compiler.coreLibrary, compiler);
   return library;
 }
 
 class StringScript extends Script {
   final String code;
   StringScript(this.code) : super(null, null);
   String get text() => code;
   String get name() => "mock script";
 }