Fix accessor map transitions vs. Object.defineProperty

test/mjsunit/regress/regress-4534.js

+// 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: --allow-natives-syntax --expose-gc
+
+var dp = Object.defineProperty;
+function getter() { return 111; }
+function setter(x) { print(222); }
+obj1 = {};
+dp(obj1, "golf", { get: getter, configurable: true });
+dp(obj1, "golf", { set: setter, configurable: true });
+gc();
+obj2 = {};
+dp(obj2, "golf", { get: getter, configurable: true });
+dp(obj2, "golf", { set: setter, configurable: true });
+assertTrue(%HaveSameMap(obj1, obj2));