DatePicker: close timepicker before dodestroy

packages/date-picker/src/panel/date.vue

 <template>
-  <transition name="el-zoom-in-top" @after-leave="$emit('dodestroy')">
+  <transition name="el-zoom-in-top" @after-leave="afterLeave">
     <div
       v-show="visible"
       :style="{
@@ -342,6 +342,11 @@
           this.year = this.date.getFullYear();
           this.month = this.date.getMonth();
         }
+      },
+
+      afterLeave() {
+        this.$refs.timepicker.handleConfirm();
+        this.$emit('dodestroy');
       }
     },