title: Vue.js child component event sometimes will not fire
body: <p>I have a component A use v-for render multiple component B, in component B
  fire an animationend to A, and in A delete that B</p>
  
  <p>but sometime the animationend won't fire</p>
  
  <p><a href="https://codesandbox.io/s/animationend-problem-zkgkh" rel="nofollow noreferrer">code sandbox</a></p>