Fixed spec violation of storing to length of a frozen object.

test/mjsunit/regress/regress-crbug-350890.js

+// Copyright 2014 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
+
+function set_length(a, l) {
+  a.length = l;
+}
+
+function test1() {
+  var l = {};
+  var a = Array(l);
+  set_length(a, 3);
+  set_length(a, 3);
+  assertEquals(3, a.length);
+}
+
+function test2() {
+  var a = [];
+  set_length(a, 10);
+  set_length(a, 10);
+  Object.freeze(a);
+  set_length(a, 3);
+  set_length(a, 3);
+  assertEquals(10, a.length);
+}
+
+function test3() {
+  var a = [2];
+  Object.defineProperty(a, "length", {value:2, writable: false});
+  %ToFastProperties(a);
+  set_length([], 10);
+  set_length([], 10);
+  set_length(a, 10);
+  set_length(a, 10);
+  assertEquals(2, a.length);
+}
+
+test1();
+test2();
+test3();