Remove all harmony runtime flags which shipped in M51

test/mjsunit/regress/regress-crbug-600995.js

Index: test/mjsunit/regress/regress-crbug-600995.js
diff --git a/test/mjsunit/regress/regress-crbug-600995.js b/test/mjsunit/regress/regress-crbug-600995.js
deleted file mode 100644
index c532608799f59c98aa1642abdf416a9560cf2cc1..0000000000000000000000000000000000000000
--- a/test/mjsunit/regress/regress-crbug-600995.js
+++ /dev/null
@@ -1,10 +0,0 @@
-// 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.
-
-// Flags: --noharmony-iterator-close
-
-// The {Set} function will produce a different type feedback vector layout
-// depending on whether Harmony iterator finalization is enabled or not.
-
-new Set();