Remove --harmony-array-includes flag

test/mjsunit/harmony/array-includes-to-object-strict.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.
-
-// Flags: --harmony-array-includes
-
-// Ported from
-// https://github.com/tc39/Array.prototype.includes/blob/master/test/number-this.js
-// using https://www.npmjs.org/package/test262-to-mjsunit
-
-// Array.prototype.includes should use ToObject on this, so that when called
-// with a number, it picks up numeric properties from Number.prototype (even in
-// strict mode)
-(function() {
-  "use strict";
-
-  Number.prototype[0] = "a";
-  Number.prototype[1] = "b";
-
-  Object.defineProperty(Number.prototype, 2, {
-    get: function() {
-      assertEquals("object", typeof this);
-      return "c";
-    }
-  });
-
-  Number.prototype.length = 3;
-  assertTrue(Array.prototype.includes.call(5, "a"));
-  assertTrue(Array.prototype.includes.call(5, "b"));
-  assertTrue(Array.prototype.includes.call(5, "c"));
-  assertFalse(Array.prototype.includes.call(5, "d"));
-})();