title: Angular-material md-virtual-repeat I get the same count of watchers, why?
body: <p>I try to understand <a href="https://material.angularjs.org/latest/api/directive/mdVirtualRepeat" rel="nofollow">md-virtual-repeat</a> purpose and for some reason I don't see the difference with single <code>md-list</code> and <code>ng-repeat</code>.</p>
  
  <blockquote>
    <p>Virtual repeat is a limited substitute for ng-repeat that renders only
    enough dom nodes to fill the container and recycling them as the user
    scrolls. Arrays, but not objects are supported for iteration. </p>
  </blockquote>
  
  <p>I have huge list of items and I use Chrome watcher count to see the improvements.</p>
  
  <p>Before I used <code>ng-repeat</code> and I got ~4000 of watchers. However when I migrated to <code>md-virtual-repeat</code> I got the same 4K of watchers.</p>
  
  <pre><code>&lt;md-virtual-repeat-container id="vertical-container"&gt;
        &lt;div md-virtual-repeat="agenda in ctrl.items"  &gt;
           &lt;span ng-if="::agenda.isDivider" style="margin-left: 5px;"&gt;
                          &lt;span&gt;
                              {{agenda.title.day}}
                          &lt;/span&gt;
                          &lt;span&gt;
                              {{agenda.title.date}}
                          &lt;/span&gt;
                      &lt;/span&gt;
  
  
                      &lt;div ng-if="::!agenda.isDivider"  
                            flex layout="row" layout-align="start center"&gt;
                         ...
                     &lt;/div&gt;
  </code></pre>
  
  <p>do I miss something?</p>
  
  <p>This is an example I play with: <a href="http://codepen.io/anon/pen/BKaNeN?editors=1010" rel="nofollow">Codepan</a></p>