// Copyright 2018 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./* Test behaviors when the prototype has elements */// lastIndexOf(function(){vararray=[,];functionlastIndexOf(val){returnarray.lastIndexOf(val);}assertEquals(lastIndexOf(6),-1);array.__proto__.push(6);assertEquals(lastIndexOf(6),0);})();