pkg/unittest: much cleaner support for arbitrary args in expectAsync functions

pkg/unittest/test/test_utils.dart

Index: pkg/unittest/test/test_utils.dart
diff --git a/pkg/unittest/test/test_utils.dart b/pkg/unittest/test/test_utils.dart
index de783bedcf09abf5b13449ad96ef732a592f9b73..783f71ba91839e7310c9a119de5fb3e36d5906c2 100644
--- a/pkg/unittest/test/test_utils.dart
+++ b/pkg/unittest/test/test_utils.dart
@@ -36,7 +36,7 @@ void shouldFail(value, Matcher matcher, expected, {bool isAsync: false}) {
     if (expected is String) {
       expect(errorString, equalsIgnoringWhitespace(expected));
     } else {
-     expect(errorString.replaceAll('\n',''), expected);
+      expect(errorString.replaceAll('\n', ''), expected);
     }
   }