[Isolates] Merge 6700:7030 from bleeding_edge to isolates.

test/mjsunit/regress/regress-1172.js

 // Copyright 2011 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 19 matching lines @@
 
 // Note: no setters would lead to runtime exception if we ever attempt
 // to use JS accessors to set 'constructor' property.
 Object.prototype.__defineGetter__('constructor', function() { throw 42; });
 
 function f() {}
 assertSame(f, f.prototype.constructor);
 
 var o = new f();
 assertSame(f, o.constructor);