Merge two constants.dart into one.

pkg/analysis_server/lib/src/edit/edit_domain.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 edit.domain;
 
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/computer/error.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/edit/fix.dart';
 import 'package:analysis_server/src/protocol.dart';
-import 'package:analysis_server/src/services/constants.dart';
 import 'package:analysis_server/src/services/correction/assist.dart';
 import 'package:analysis_server/src/services/correction/change.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analysis_server/src/services/json.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart' as engine;
 import 'package:analyzer/src/generated/error.dart' as engine;
@@ skipping 105 matching lines @@
 
 class RefactoringKind {
   static const String CONVERT_GETTER_TO_METHOD = 'CONVERT_GETTER_TO_METHOD';
   static const String CONVERT_METHOD_TO_GETTER = 'CONVERT_METHOD_TO_GETTER';
   static const String EXTRACT_LOCAL_VARIABLE = 'EXTRACT_LOCAL_VARIABLE';
   static const String EXTRACT_METHOD = 'EXTRACT_METHOD';
   static const String INLINE_LOCAL_VARIABLE = 'INLINE_LOCAL_VARIABLE';
   static const String INLINE_METHOD = 'INLINE_METHOD';
   static const String RENAME = 'RENAME';
 }