title: iAd banners producing blank space when using canDisplayBannerAds on UITableView
body: <p>I have a UITableView that I'm calling <code>self.canDisplayBannerAds = YES</code> in <code>viewDidAppear</code>. When the ads display, extra space appears at the bottom of the table view equal to the height of the iAd. When the ad hides, the extra space vanishes.</p>
  
  <p>Just to note, I am using AutoLayout.</p>
  
  <p>For complete clarification, here is the only piece of code relating to iAd in my entire project:</p>
  
  <pre><code>- (void)viewDidAppear:(BOOL)animated {
  [super viewDidAppear:animated];
  
      self.canDisplayBannerAds = YES;
  }
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/rbUCw.png" alt="Image showing relevant problem"></p>
  
  <p>I've got no idea what could be causing this. I've tried moving the <code>canDisplayBannerAds</code> around to no avail.</p>