Remove runtime flags for Proxy and Reflect

test/mjsunit/es6/proxies-delete-property.js

 // Copyright 2015 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-proxies --harmony-reflect
-
 
 var properties =
     ["bla", "0", 1, Symbol(), {[Symbol.toPrimitive]() {return "a"}}];
 
 
 function TestForwarding(handler, myDelete, shouldThrow) {
   var target = {};
   var proxy = new Proxy(target, handler);
 
   assertFalse(target.hasOwnProperty("doesnotexist"));
@@ skipping 164 matching lines @@
 
 
 TestTrappingFalsish(
     (o, p) => delete o[p], false);
 TestTrappingFalsish(
     (o, p) => Reflect.deleteProperty(o, p), false);
 TestTrappingFalsish(
     (o, p) => {"use strict"; return delete o[p]}, true);
 TestTrappingFalsish(
     (o, p) => {"use strict"; return Reflect.deleteProperty(o, p)}, false);