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/array-sort.js b/test/mjsunit/array-sort.js
index 36608f5..ae9f6ef 100644
--- a/test/mjsunit/array-sort.js
+++ b/test/mjsunit/array-sort.js
@@ -464,3 +464,18 @@
   assertEquals(0, Number(Array.prototype.sort.call(0)));
 }
 TestSortToObject();
+
+function TestSortOnProxy() {
+  {
+    var p = new Proxy([2,1,3], {});
+    assertEquals([1,2,3], p.sort());
+  }
+
+  {
+    function f() { return arguments };
+    var a = f(2,1,3);
+    a.__proto__ = new Proxy({}, {});
+    assertEquals([1,2,3], [...(Array.prototype.sort.apply(a))]);
+  }
+}
+TestSortOnProxy();