elementUi 日期组件ie下bug解决

问题:日期组件有初始值,有placeholder.导致第一次点击x清空 失效

1.将placehoder值,改为data动态值.

```javascript ```

2.定义变量

```javascript data() { return { rangeDate:[], startPlaceholder: '', endDatePlaceholder: '' } } ```

3.再初始化日期后,动态修改placeholder的值

```javascript this.rangeDate = ['2020-01-01','2020-02-02']; this.$nextTick(() => { this.startPlaceholder = '开始日期'; this.endDatePlaceholder = '结束日期'; }); ```

注:仅在ie下,有placehoder,且date组件有初始值才会有这个问题