Add regression tests.

test/kernel/regression/issue_000044.dart

Index: test/kernel/regression/issue_000044.dart
diff --git a/test/kernel/regression/issue_000033.dart b/test/kernel/regression/issue_000044.dart
similarity index 92%
copy from test/kernel/regression/issue_000033.dart
copy to test/kernel/regression/issue_000044.dart
index cf8392bf21615edd1992f8ad034d463cc12882f4..95145f5dbd4283e587568d2283e554163dd859a7 100644
--- a/test/kernel/regression/issue_000033.dart
+++ b/test/kernel/regression/issue_000044.dart
@@ -2,6 +2,4 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
-@JS()
-main() {
-}
+a b(c) = d;