title: Why is my ad not showing when I run the test on the IOS simulator?
body: <p>I hooked up my app with adMob. When I run the tests on the ios simulator no test ad appears. Also my app is now slower and glitchier. What is wrong? This is in my <code>viewDidLoad</code> function</p>
  
  <pre><code>    let request = GADRequest()
      request.testDevices = [kGADSimulatorID]
      bannerView.delegate = self
      bannerView.adUnitID = "ca-app-pub-4520288405399190/1979194331"
      bannerView.rootViewController = self
      bannerView.load(request)
  </code></pre>