[turbofan] Fix context chain extension for top-level code.

test/mjsunit/regress/regress-4169.js

Index: test/mjsunit/regress/regress-4169.js
diff --git a/test/message/super-in-function.js b/test/mjsunit/regress/regress-4169.js
similarity index 68%
copy from test/message/super-in-function.js
copy to test/mjsunit/regress/regress-4169.js
index edaa0e4eadc7befdb7ed28a3e06eaa827c4388f0..df2de039844fd748c9b83d61608cef5f8c09e181 100644
--- a/test/message/super-in-function.js
+++ b/test/mjsunit/regress/regress-4169.js
@@ -1,10 +1,9 @@
 // Copyright 2015 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.
-//
-// Flags: --harmony-classes
-'use strict';
 
-function f() {
-  super.x();
+with ({}) {
+  eval("var x = 23");
+  assertEquals(23, x);
 }
+assertEquals(23, x);