title: Make a flexbox child div 50% width and grow to 100% on wrap
body: <p>I have the following</p>
  
  <pre><code>&lt;div style="max-width:100%;flex-wrap:wrap;display:flex"&gt;
     &lt;div style="width:50%;flex-grow:1"&gt;&lt;/div&gt;
     &lt;div style="width:50%;flex-grow:1"&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>What I'm trying to do is to have the two child elements start off at 50% width.  When the window size is reduced, I want the second one to wrap below the first one and both of them to grow to 100%.  Right now the first one is starting of at 100%.  I'm using Chrome.</p>