title: iOS11 photo library access is possible even if settings are set to "never"
body: <pre><code>if UIImagePickerController.isSourceTypeAvailable(.photoLibrary) {
      let imagePicker = UIImagePickerController()
      imagePicker.sourceType = .photoLibrary
      imagePicker.allowsEditing = true
      self.present(imagePicker, animated: true, completion: { })
  }
  </code></pre>
  
  <p>Even if I set access to Photos in Settings to "Never" with above code I can still present image picker and show photos. I'll check for <code>PHPhotoLibrary.authorizationStatus()</code> before showing it, but I would like to know is this expected behaviour?</p>