Simplify test_suite.dart.

tools/testing/dart/co19_test.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.
 
 /**
  * Tool for running co19 tests. Used when updating co19.
  *
  * Currently, this tool is merely a convenience around multiple
  * invocations of test.dart. Long term, we hope to evolve this into a
  * script that can automate most of the tasks necessary when updating
  * co19.
  *
  * Usage:
  * [: dart tools/testing/dart/co19_test.dart :]
  */
 
 import 'dart:io';
 
 import 'configuration.dart';
 import 'options.dart';
-import 'test_suite.dart';
 import 'test_configurations.dart';
+import 'utils.dart';
 
 const List<String> COMMON_ARGUMENTS = const <String>[
   '--report',
   '--progress=diff',
   'co19'
 ];
 
 const List<List<String>> COMMAND_LINES = const <List<String>>[
   const <String>['-mrelease,debug', '-rvm', '-cnone'],
   const <String>['-mrelease,debug', '-rvm', '-cnone', '--checked'],
@@ skipping 32 matching lines @@
     arguments.addAll(COMMON_ARGUMENTS);
     arguments.addAll(args);
     arguments.addAll(commandLine);
     configurations.addAll(optionsParser.parse(arguments));
   }
 
   if (configurations != null || configurations.length > 0) {
     testConfigurations(configurations);
   }
 }