【报Bug】video层级问题（ios12.1.4, ios12.2最新版本有bug）

<view class="openScreen">  
        <view class="skip" @click="skip"><text class="number">{{number}}</text>跳过广告</view>  
        <view class="content" v-if="pageHomeAd.type == 'img'" :style="{height: height + 'px', background: 'url('+ pageHomeAd.typeLink + ') no-repeat center', backgroundSize: 'auto 100%'}" @click="revisePageAd"></view>  
        <view class="content" :style="{height: height + 'px'}" v-else @click="revisePageAd">  
            <video :src="pageHomeAd.typeLink" :controls="false" :autoplay="false" :show-center-play-btn="false" objectFit="cover" :duration="5"></video>  
        </view>  
        <view class="footer">  
            <view>  
                <view class="titleName">小黄历.大精彩</view>  
                <view class="titleText">Copyright©2017 mdollar</view>  
                <view class="titleText">All rights reserved</view>  
            </view>  
        </view>  
        <view class="fromPage" v-show="isEdit">  
            <view class="editTitle">编辑</view>  
            <view class="itemPage">  
                <view class="title">类型:</view>  
                <radio-group name="radio" class="radioContent" @change="radioChange">  
                    <label class="radio" v-for="(item, index) in itemType" :key="index"><radio value="item.type" :checked="item.checked" color="#ff5738"/>{{item.value}}</label>  
                </radio-group>  
            </view>  
            <view class="itemPage">  
                <view class="title">图片/视频链接:</view>  
                <view class="upload">  
                    <view class="linkfile" @click="linkTo(linkFile)" v-show="linkFile != '上传图片生成链接' && linkFile != ''">{{linkFile != '上传图片生成链接' && linkFile != '' ? '查看图片' : ''}}</view>  
                    <button type="primary" size="mini" @click="fileUpload" :style="{backgroundColor: '#ff5738'}">上传文件</button>  
                </view>  
            </view>  
            <view class="itemPage">  
                <view class="title">链接:</view>  
                <input name="input" placeholder="输入链接" v-model="link" class="link"/>  
            </view>  
            <view class="submit">  
                <button type="default" size="mini" @click="submit">提交</button>  
            </view>  
        </view>  
    </view>
```## 详细问题描述  
跳转按钮，中间弹窗都存在，在ios12.2中，都消失  
![无bug图](http://statich.yidianzixun.com/public/file/1555384980751/1555384538078.jpg)  
![有bug图，video在最上面](http://statich.yidianzixun.com/public/file/1555384980751/WechatIMG1.png)