Merge 6006:6095 from bleeding_edge to experimental/gc branch.

test/mjsunit/regress/regress-687.js

 // Copyright 2009 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 55 matching lines @@
 
 var obj2 = { get p() {}};
 Object.defineProperty(obj2, 'p', {get: undefined})
 assertTrue("p" in obj2);
 desc = Object.getOwnPropertyDescriptor(obj2, "p");
 assertTrue(desc.configurable);
 assertTrue(desc.enumerable);
 assertEquals(desc.value, undefined);
 assertEquals(desc.get, undefined);
 assertEquals(desc.set, undefined);