Upgrade V8 to 5.1.281.57  DO NOT MERGE

FPIIM-449

Change-Id: Id981b686b4d587ac31697662eb98bb34be42ad90
(cherry picked from commit 3b9bc31999c9787eb726ecdbfd5796bfdec32a18)
diff --git a/test/mjsunit/es6/typedarray-of.js b/test/mjsunit/es6/typedarray-of.js
index a6df29a..eaa7bde 100644
--- a/test/mjsunit/es6/typedarray-of.js
+++ b/test/mjsunit/es6/typedarray-of.js
@@ -115,9 +115,9 @@
   // Check superficial features of %TypedArray%.of.
   var desc = Object.getOwnPropertyDescriptor(constructor.__proto__, "of");
 
-  assertEquals(desc.configurable, false);
+  assertEquals(desc.configurable, true);
   assertEquals(desc.enumerable, false);
-  assertEquals(desc.writable, false);
+  assertEquals(desc.writable, true);
   assertEquals(constructor.of.length, 0);
 
   // %TypedArray%.of is not a constructor.