title: beforeRouteEnter does not set value on 2nd visit
body: <p>Short explanation:</p>
  
  <ul>
  <li>first load = ok</li>
  <li>press back, then press forward (or go to other route and get back to the previous)</li>
  <li>second load = no data</li>
  </ul>
  
  <p>Long explanation:</p>
  
  <p>I have a very simple code inside beforeRouteEnter. I just fetch using axios, use <code>then</code>, execute <code>next(vm =&gt; .....)</code> inside.</p>
  
  <p>First load, data are being set. e.g <code>vm.someData = 'value'</code>
  Second time that route is visited, <code>someData</code> is empty. Not set.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Tried to remove axios to see if it's really the <code>router</code>. Here's the code</p>
  
  <p><code>beforeRouteEnter (...) {
   next(vm =&gt; vm.someData = 'data')
  }
  </code></p>
  
  <p><code>someData</code> is still empty on second visit</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Saw the bottom part of <a href="https://router.vuejs.org/en/advanced/data-fetching.html" rel="nofollow noreferrer">https://router.vuejs.org/en/advanced/data-fetching.html</a></p>
  
  <p>I followed the <code>watch</code> part but it doesn't even react at all.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Seems like a bug: <a href="https://github.com/vuejs/vue-router/issues/1322" rel="nofollow noreferrer">https://github.com/vuejs/vue-router/issues/1322</a></p>