'Rename Local Variable' refactoring implementation.

pkg/analysis_services/lib/src/refactoring/refactoring.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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library services.src.refactoring;
 
+import 'dart:async';
+
 import 'package:analysis_services/correction/status.dart';
 import 'package:analysis_services/refactoring/refactoring.dart';
 
 
 /**
- * Abstract implementation of {@link Refactoring}.
+ * Abstract implementation of [Refactoring].
  */
 abstract class RefactoringImpl implements Refactoring {
   @override
-  RefactoringStatus checkAllConditions() {
+  Future<RefactoringStatus> checkAllConditions() {
     RefactoringStatus result = new RefactoringStatus();
-    result.addStatus(checkInitialConditions());
-    if (!result.hasFatalError) {
-      result.addStatus(checkFinalConditions());
-    }
-    return result;
+    return checkInitialConditions().then((status) {
+      result.addStatus(status);
+      if (result.hasFatalError) {
+        return result;
+      }
+      return checkFinalConditions().then((status) {
+        result.addStatus(status);
+        return result;
+      });
+    });
   }
 }