Guard the property RegExp.prototype.unicode behind --harmony-regexp-unicode

src/js/harmony-regexp.js

 // Copyright 2014 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.
 
 (function(global, utils) {
 
 'use strict';
 
 %CheckIsBootstrapping();
 
@@ skipping 38 matching lines @@
       %IncrementUseCounter(kRegExpPrototypeStickyGetter);
       return UNDEFINED;
     }
     throw MakeTypeError(kRegExpNonRegExp, "RegExp.prototype.sticky");
   }
   return !!REGEXP_STICKY(this);
 }
 %FunctionSetName(RegExpGetSticky, "RegExp.prototype.sticky");
 %SetNativeFlag(RegExpGetSticky);
 
-
-// ES6 21.2.5.15.
-function RegExpGetUnicode() {
-  if (!IS_REGEXP(this)) {
-    throw MakeTypeError(kRegExpNonRegExp, "RegExp.prototype.unicode");
-  }
-  return !!REGEXP_UNICODE(this);
-}
-%FunctionSetName(RegExpGetUnicode, "RegExp.prototype.unicode");
-%SetNativeFlag(RegExpGetUnicode);
-
 utils.InstallGetter(GlobalRegExp.prototype, 'flags', RegExpGetFlags);
 utils.InstallGetter(GlobalRegExp.prototype, 'sticky', RegExpGetSticky);
-utils.InstallGetter(GlobalRegExp.prototype, 'unicode', RegExpGetUnicode);
 
 })