title: How to notify List component that one item has changed the size?
body: <p>I would like to render a list of items using react-virtualized, however some of the items could change the size.</p>
  
  <p>I have added a demo, where each item has a button and when someone clicks the button then the item needs to expand and push the below items lower:
  <a href="https://plnkr.co/edit/GG2bSIC5M1Gj7BR1pOii" rel="noreferrer">https://plnkr.co/edit/GG2bSIC5M1Gj7BR1pOii</a></p>
  
  <p>The use case is similar to facebook posts, when someone comments it will expand the post and push the other posts lower.</p>
  
  <pre><code>ReactDOM.render(
  &lt;List
  className='List'
  autoHeight
  width={300}
  height={400}
  rowCount={list.length}
  rowHeight={30}
  rowRenderer={
    ({ index, isScrolling, key, style }) =&gt; (
      &lt;div
        className='Row'
        key={key}
        style={style}
      &gt;
        {list[index]}
        &lt;Expander /&gt;  /* contains the button, which when click it will expand more text*/
      &lt;/div&gt;
    )
  }
  /&gt;,
  document.getElementById('example')
  </code></pre>
  
  <p>Is any way to achieve this?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>I am realizing that there must be a way to force the <code>List</code> to update items and recalculate positions. There is an example with <code>InfiniteLoader</code> (<a href="https://github.com/bvaughn/react-virtualized/blob/master/source/InfiniteLoader/InfiniteLoader.example.js" rel="noreferrer">react-virtualized example</a>) which is using <code>registerChild</code> in the List as a ref. And it seems that when InfiniteLoader receives answer from the server it capable of forcing list to re-render rows.</p>
  
  <p>I have tried another example with <code>forceUpdate</code> on list, however the List is still not updating.</p>
  
  <p><a href="https://plnkr.co/edit/RftoShEkQW5MR5Rl28Vu" rel="noreferrer">https://plnkr.co/edit/RftoShEkQW5MR5Rl28Vu</a></p>