title: TableView pushed down after view change
body: <p>I'm kind of new with ios development with swift 4, so I'm testing some functionalities.
  I have a tableview inside a normal <code>UIViewController</code>: <a href="https://i.stack.imgur.com/B0OVY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/B0OVY.png" alt="tableviewlayout"></a></p>
  
  <p>The space left blank is intentionally, as I have some custom tabs.</p>
  
  <p>When I show a detail from a table cell element, and then press back button, the table view gets pushed down (and up). Please see <a href="http://gph.is/2EJJCkv" rel="nofollow noreferrer">this</a> where I show the problem.</p>
  
  <p>The iphone is a SE with ios10. <strong>In simulations with iOS11, this does not happen.</strong> Developing in MacOS Sierra 10.12.6 with xCode 9.2.</p>
  
  <p>Any clue on how to fix this? </p>
  
  <p>EDIT:</p>
  
  <p>Using the view debugger, I got this:
  <a href="https://i.stack.imgur.com/CVkd4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CVkd4.png" alt="viewdebugger"></a></p>
  
  <p>The selected area is a <code>UITableWrapperView</code> element. Behind it, is the <code>UITableView</code>, which preserve its constrains. </p>