Remove all harmony runtime flags which shipped in M51

test/mjsunit/harmony/instanceof-es6.js

-// 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: --harmony-instanceof
-
-// Make sure it's an error if @@hasInstance isn't a function.
-(function() {
-  var F = {};
-  F[Symbol.hasInstance] = null;
-  assertThrows(function() { 0 instanceof F; }, TypeError);
-})();
-
-// Make sure the result is coerced to boolean.
-(function() {
-  var F = {};
-  F[Symbol.hasInstance] = function() { return undefined; };
-  assertEquals(0 instanceof F, false);
-  F[Symbol.hasInstance] = function() { return null; };
-  assertEquals(0 instanceof F, false);
-  F[Symbol.hasInstance] = function() { return true; };
-  assertEquals(0 instanceof F, true);
-})();
-
-// Make sure if @@hasInstance throws, we catch it.
-(function() {
-  var F = {};
-  F[Symbol.hasInstance] = function() { throw new Error("always throws"); }
-  try {
-    0 instanceof F;
-  } catch (e) {
-    assertEquals(e.message, "always throws");
-  }
-})();
-
-// @@hasInstance works for bound functions.
-(function() {
-  var BC = function() {};
-  var bc = new BC();
-  var bound = BC.bind();
-  assertEquals(bound[Symbol.hasInstance](bc), true);
-  assertEquals(bound[Symbol.hasInstance]([]), false);
-})();
-
-// if OrdinaryHasInstance is passed a non-callable receiver, return false.
-assertEquals(Function.prototype[Symbol.hasInstance].call(Array, []), true);
-assertEquals(Function.prototype[Symbol.hasInstance].call({}, {}), false);
-
-// OrdinaryHasInstance passed a non-object argument returns false.
-assertEquals(Function.prototype[Symbol.hasInstance].call(Array, 0), false);
-
-// Cannot assign to @@hasInstance with %FunctionPrototype%.
-(function() {
-  "use strict";
-  function F() {}
-  assertThrows(function() { F[Symbol.hasInstance] = (v) => v }, TypeError);
-})();
-
-// Check correct invocation of @@hasInstance handler on function instance.
-(function() {
-  function F() {}
-  var counter = 0;
-  var proto = Object.getPrototypeOf(F);
-  Object.setPrototypeOf(F, null);
-  F[Symbol.hasInstance] = function(v) { ++counter; return true };
-  Object.setPrototypeOf(F, proto);
-  assertTrue(1 instanceof F);
-  assertEquals(1, counter);
-})();