Update test.dart for detection output of machine formatted errors

tools/testing/dart/test_suite.dart

Index: tools/testing/dart/test_suite.dart
diff --git a/tools/testing/dart/test_suite.dart b/tools/testing/dart/test_suite.dart
index 2c292945b8337f6703932e78d41d416c6b4811aa..91b8003343e04e32293cad7f041c73bd0d75c4c6 100644
--- a/tools/testing/dart/test_suite.dart
+++ b/tools/testing/dart/test_suite.dart
@@ -712,8 +712,12 @@ class StandardTestSuite implements TestSuite {
                                            bool enableFatalTypeErrors) {
     List args = TestUtils.standardOptions(configuration);
     args.addAll(additionalOptions(filename));
-    if (enableFatalTypeErrors && configuration['component'] == 'dartc') {
-      args.add('--fatal-type-errors');
+    if (configuration['component'] == 'dartc') {
+      args.add('--error_format');
+      args.add('machine');
+      if (enableFatalTypeErrors) {
+        args.add('--fatal-type-errors');
+      }
     }
 
     bool isMultitest = optionsFromFile["isMultitest"];