Upgrade V8 to 5.1.281.57  DO NOT MERGE

FPIIM-449

Change-Id: Id981b686b4d587ac31697662eb98bb34be42ad90
(cherry picked from commit 3b9bc31999c9787eb726ecdbfd5796bfdec32a18)
diff --git a/test/message/message.status b/test/message/message.status
index 234bf0f..051911c 100644
--- a/test/message/message.status
+++ b/test/message/message.status
@@ -29,5 +29,9 @@
 [ALWAYS, {
   # All tests in the bug directory are expected to fail.
   'bugs/*': [FAIL],
+  # We don't parse RegExps at scanning time, so we can't fail on octal
+  # escapes (we need to parse to distinguish octal escapes from valid
+  # back-references).
+  'strict-octal-regexp': [SKIP],
 }],  # ALWAYS
 ]