Properly disallow 'yield' in class expressions and arrow parameters

test/message/yield-in-arrow-param.js

Index: test/message/yield-in-arrow-param.js
diff --git a/test/message/regress/regress-4829-1.js b/test/message/yield-in-arrow-param.js
similarity index 82%
copy from test/message/regress/regress-4829-1.js
copy to test/message/yield-in-arrow-param.js
index 1ad5feda8cb96cd24e4c47f7407c9699d150c327..c815fe7603ea27a1279f8713b36c3a0d988abfb6 100644
--- a/test/message/regress/regress-4829-1.js
+++ b/test/message/yield-in-arrow-param.js
@@ -2,6 +2,4 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-function tag() {}
-
-tag(tag`\xyy`);
+function* g() { (a = yield) => {} }