title: UISearchBar's set_cancelButtonText: ivar is prohibited
body: <p>Previously in iOS 12 the same code was allowed, but now when i try to run the same code on iOS 13 it crashes giving me the same error:</p>
  
  <blockquote>
    <p>Terminating app due to uncaught exception 'NSGenericException',
    reason: 'Access to UISearchBar's set_cancelButtonText: ivar is
    prohibited. This is an application bug'</p>
  </blockquote>
  
  <p>Which is related to this line of code: </p>
  
  <pre><code>searchController.searchBar.setValue("Cancel".localized, forKey:"_cancelButtonText")
  </code></pre>
  
  <p>Now i know the access of setValue is now prohibited but how is it possible to overcome this crash and change the title of cancel button, since there is no property included in the searchbar.</p>