Revert "Replace the configuration map with a typed object."

tools/testing/dart/co19_test_config.dart

Index: tools/testing/dart/co19_test_config.dart
diff --git a/tools/testing/dart/co19_test_config.dart b/tools/testing/dart/co19_test_config.dart
index 908d216f86b493f3caa3de7d0a9633e346d1ab7e..f16298cf08cf0b3bcecf03461281ab96b477e7eb 100644
--- a/tools/testing/dart/co19_test_config.dart
+++ b/tools/testing/dart/co19_test_config.dart
@@ -2,14 +2,15 @@
 // 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.
 
-import 'configuration.dart';
+library co19_test_config;
+
 import 'path.dart';
 import 'test_suite.dart';
 
 class Co19TestSuite extends StandardTestSuite {
   RegExp _testRegExp = new RegExp(r"t[0-9]{2}.dart$");
 
-  Co19TestSuite(Configuration configuration)
+  Co19TestSuite(Map<String, dynamic> configuration)
       : super(configuration, "co19", new Path("tests/co19/src"), [
           "tests/co19/co19-co19.status",
           "tests/co19/co19-analyzer.status",