Revert "Revert "Refactor test option parsing code.""

tools/testing/dart/package_testing_support.dart

Index: tools/testing/dart/package_testing_support.dart
diff --git a/tools/testing/dart/package_testing_support.dart b/tools/testing/dart/package_testing_support.dart
index d470663538494cd9cbbbbdcba19f6c9d3a0ec86d..913d6282356d2652b2ccdfbdfb179bbfb93f2140 100644
--- a/tools/testing/dart/package_testing_support.dart
+++ b/tools/testing/dart/package_testing_support.dart
@@ -4,17 +4,15 @@
 
 library package_testing_support;
 
-import 'test_configurations.dart' show testConfigurations;
-
-import 'test_options.dart' show TestOptionsParser;
-
-import 'test_suite.dart' show TestUtils;
+import 'options.dart';
+import 'test_configurations.dart';
+import 'test_suite.dart';
 
 void main(List<String> arguments) {
   TestUtils.setDartDirUri(Uri.base);
   var configurations = <Map>[];
   for (var argument in arguments) {
-    configurations.addAll(new TestOptionsParser().parse(argument.split(" ")));
+    configurations.addAll(new OptionsParser().parse(argument.split(" ")));
   }
   testConfigurations(configurations);
 }