Reorganize equivalence test helpers

tests/compiler/dart2js/serialization/resolved_ast_test.dart

Index: tests/compiler/dart2js/serialization/resolved_ast_test.dart
diff --git a/tests/compiler/dart2js/serialization/resolved_ast_test.dart b/tests/compiler/dart2js/serialization/resolved_ast_test.dart
index f18a7b64cf019073d3debd5fa68e3148fcc6227e..7b2fd20a34eacf5ce1aee7b6820cfdd302037d36 100644
--- a/tests/compiler/dart2js/serialization/resolved_ast_test.dart
+++ b/tests/compiler/dart2js/serialization/resolved_ast_test.dart
@@ -8,13 +8,11 @@ import 'dart:async';
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/commandline_options.dart';
 import 'package:compiler/src/compiler.dart';
-import 'package:compiler/src/elements/elements.dart';
 import 'package:compiler/src/filenames.dart';
-import 'package:compiler/src/serialization/equivalence.dart';
+import '../equivalence/check_functions.dart';
 import '../memory_compiler.dart';
 import 'helper.dart';
 import 'test_data.dart';
-import 'test_helper.dart';
 
 main(List<String> args) {
   Arguments arguments = new Arguments.from(args);