weex recyle-list如果有事件沖突在IOS會導致程序崩潰

1、當recycle-list內部綁定了一個click事件，在recycle-list結構外部，用fixed定位的元素上面再綁定一個click事件會導致頁面崩潰。下面代碼是recycle-list的demo上面一點改動，直接運行在IOS，WEEX-Playground上面會崩潰
2、`

<template>
    <div>
        <recycle-list class="list" for="(cell, i) in counters">
            <cell-slot>
                <div class="counter"  @appear="toast(i)">
                    <text class="output">{{cell.count}}</text>
                    <text class="button" @click="inc(i)">+</text>
                    <text class="index">index: {{i}}</text>
                </div>
            </cell-slot>
        </recycle-list>
        <!-- todo:放到list里面,會偶然性地被隱藏掉。-->
        <image class="go-top" src="http://img.alicdn.com/tps/TB1zBLaPXXXXXXeXXXXXXXXXXXX-121-59.svg" @click="toast(1)"></image>
    </div>
</template>

<script>
    const modal = weex.requireModule('modal')
    export default {
        data () {
            let start = 1, N = 100
            const counters = []
            while (N--) {
                counters.push({ count: start++ })
            }
            return { counters }
        },
        methods: {
            inc (index) {
                if (!this.counters[index]) return;
                this.counters[index].count++
            },
            toast (i) {
                modal.toast({ message: `appear ${i}: ${this.counters[i].count}` })
            }
        }
    }
</script>

<style scoped>
    .list { width: 750px; }
    .counter {
        position: relative;
        border-top-width: 1px;
        border-top-style: solid;
        border-top-color: #DDD;
        margin-bottom: 80px;
    }
    .index {
        position: absolute;
        top: 10px;
        left: 20px;
        color: #BBB;
        font-size: 30px;
    }
    .output {
        font-size: 150px;
        text-align: center;
        padding: 50px;
        background-color: #FBFBFB;
    }
    .button {
        border-width: 2px;
        border-color: #DDD;
        font-size: 100px;
        text-align: center;
        background-color: #F5F5F5;
    }
    /* 回到頂部  */
    .go-top{
        position: fixed;
        right: 15wx;
        bottom: 90wx;
        width: 38wx;
        height: 38wx;
    }
</style>

`