Remove all harmony runtime flags which shipped in M51

test/mjsunit/regress/regress-crbug-605862.js

Index: test/mjsunit/regress/regress-crbug-605862.js
diff --git a/test/mjsunit/regress/regress-crbug-605862.js b/test/mjsunit/regress/regress-crbug-605862.js
index 3124c0647f1c883a84b073dfd0c1af73ffdc856c..82a5d454ec9cea5e263fbf562f73bd30a0fb7e5d 100644
--- a/test/mjsunit/regress/regress-crbug-605862.js
+++ b/test/mjsunit/regress/regress-crbug-605862.js
@@ -2,7 +2,5 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-unicode-regexps
-
 /[]*1/u.exec("\u1234");
 /[^\u0000-\u{10ffff}]*1/u.exec("\u1234");