ES6: instanceof error messages need updating.

test/message/message.status

 # Copyright 2008 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 21 matching lines @@
   # 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
 ['ignition == True', {
   # TODO(4680): Some source positions are off with Ignition.
   'default-parameter-tdz': [SKIP],
   'default-parameter-tdz-arrow': [SKIP],
   'destructuring-modify-const': [SKIP],
-  'instanceof': [SKIP],
   'overwritten-builtins': [SKIP],
   'regress/regress-1527': [SKIP],
   'regress/regress-3995': [SKIP],
   'replacement-marker-as-argument': [SKIP],
 }],  # ignition == True
 ]