[parser] better error message for generator constructors

test/message/class-constructor-generator.out

Index: test/message/class-constructor-generator.out
diff --git a/test/unittests/unittests.status b/test/message/class-constructor-generator.out
similarity index 50%
copy from test/unittests/unittests.status
copy to test/message/class-constructor-generator.out
index d439913ccf68a2b308920724a0651786bb0464da..5075e511cc753d226d832a7526b5fa5a833152e5 100644
--- a/test/unittests/unittests.status
+++ b/test/message/class-constructor-generator.out
@@ -1,6 +1,7 @@
 # Copyright 2014 the V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
-
-[
-]
+*%(basename)s:9: SyntaxError: Class constructor may not be a generator
+  *constructor() {}
+   ^^^^^^^^^^^
+SyntaxError: Class constructor may not be a generator