Revert "Revert "Upgrade to 5.0.71.48"" DO NOT MERGE

This reverts commit f2e3994fa5148cc3d9946666f0b0596290192b0e,
and updates the x64 makefile properly so it doesn't break that
build.

FPIIM-449

Change-Id: Ib83e35bfbae6af627451c926a9650ec57c045605
(cherry picked from commit 109988c7ccb6f3fd1a58574fa3dfb88beaef6632)
diff --git a/test/mjsunit/es6/classes-super.js b/test/mjsunit/es6/classes-super.js
new file mode 100644
index 0000000..7bdf4ba
--- /dev/null
+++ b/test/mjsunit/es6/classes-super.js
@@ -0,0 +1,15 @@
+// Copyright 2016 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.
+
+"use strict";
+
+class Test {
+  m() {
+    super.length = 10;
+  }
+}
+
+var array = [];
+Test.prototype.m.call(array);
+assertEquals(10, array.length);