title: UISearchController: show results even when search bar is empty
body: <p>As I understand, the default behaviour of <code>UISearchController</code> is:</p>
  
  <ol>
  <li>On tapping search bar, background is dimmed and 'cancel' button is shown. <code>SearchResultsController</code> is not shown till this point.</li>
  <li><code>SearchResultsController</code> is displayed only if search bar is not empty.</li>
  </ol>
  
  <p>I want to display <code>SearchResultsController</code> even when search bar is empty but selected (i.e is case 1 above).</p>
  
  <p>Simply put, instead of background dimming, I would like to show Search results.</p>
  
  <p>Is there a way for doing this?</p>
  
  <p>More Clarification:</p>
  
  <p>I am not using <code>UISearchController</code> to filter results shown on the view on which it is shown, but some other unrelated results. 
  It will be like what facebook does on its 'News Feed'. Tapping on search bar shows search suggestions initially and then, when we start editing, it shows search results which might not be related to news feed. </p>