Move SourceReference, extract duplicate code.

pkg/analysis_server/lib/src/services/refactoring/rename_label.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 services.src.refactoring.rename_label;
 
 import 'dart:async';
 
-import 'package:analysis_server/src/protocol.dart' hide Element;
 import 'package:analysis_server/src/services/correction/status.dart';
 import 'package:analysis_server/src/services/refactoring/naming_conventions.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
 import 'package:analysis_server/src/services/refactoring/rename.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/src/generated/element.dart';
 
 
 /**
  * A [Refactoring] for renaming [LabelElement]s.
@@ skipping 15 matching lines @@
   }
 
   @override
   RefactoringStatus checkNewName() {
     RefactoringStatus result = super.checkNewName();
     result.addStatus(validateLabelName(newName));
     return result;
   }
 
   @override
-  Future<SourceChange> createChange() {
-    SourceChange change = new SourceChange(refactoringName);
-    // update declaration
-    addDeclarationEdit(change, element);
-    // update references
-    return searchEngine.searchReferences(element).then((refMatches) {
-      List<SourceReference> references = getSourceReferences(refMatches);
-      for (SourceReference reference in references) {
-        addReferenceEdit(change, reference);
-      }
-      return change;
-    });
+  Future fillChange() {
+    addDeclarationEdit(element);
+    return searchEngine.searchReferences(element).then(addReferenceEdits);
   }
 }