<div class="percorso"v-on:removeall="pathlengthTozero()">
</div>

Vue.component('lista-percorso', {
template:`
<div class="col-lg-2 col-xs-2">
    <div class="removeall pull-right" v-on:click="removeall()"></div>
</div>`,

    methods:{
    removeall : function(){
        this.listaSelezionati = [];
        this.$emit('removeall');
    }
}

pathlengthTozero : function(){
       il_tuo_percorso = [''];
    }