Remove the optimized construct stub.

test/mjsunit/regress/regress-618.js

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 66 matching lines @@
 var c4 = new C4();
 assertEquals(23, c4.x);
 assertEquals("undefined", typeof c4.y);
 
 // Add setter somewhere on the prototype chain after having constructed the
 // first instance.
 C4.prototype.__proto__.__defineSetter__('x', function(value) { this.y = 23; });
 var c4 = new C4();
 assertEquals("undefined", typeof c4.x);
 assertEquals(23, c4.y);