Fix Unicode string normalization with null bytes

test/mjsunit/regress/regress-4654.js

Index: test/mjsunit/regress/regress-4654.js
diff --git a/test/mjsunit/compiler/regress-572409.js b/test/mjsunit/regress/regress-4654.js
similarity index 62%
copy from test/mjsunit/compiler/regress-572409.js
copy to test/mjsunit/regress/regress-4654.js
index 126b622625ad4455b4bd2e309ee10e32eb02989e..eb08b1126ead9f03c67d301bd0ee332cba4c0546 100644
--- a/test/mjsunit/compiler/regress-572409.js
+++ b/test/mjsunit/regress/regress-4654.js
@@ -2,9 +2,4 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-var o = function() {};
-function f() {
-  var lit = { __proto__: o  };
-  o instanceof RegExp;
-}
-f();
+assertEquals('hello\u0000foobar', 'hello\u0000foobar'.normalize('NFC'));