title: UIScreenEdgePanGestureRecognizer
body: <p>I'm trying to implement screen edge pan gesture for my view controller. But the problem is, if trying to add edge pan gesture for two edges (UIRectEdge.left, UIRectEdge.right) as</p>
  
  <pre><code>let screenEdgePanGesture = UIScreenEdgePanGestureRecognizer.init(target: self, action: #selector(self.didPanningScreen))
  screenEdgePanGesture.edges = [.right, .left]
  screenEdgePanGesture.delegate = self
  self.view.addGestureRecognizer(screenEdgePanGesture)
  </code></pre>
  
  <p>the selector method not calling. But the edge pan gesture is working for one edge i.e.,</p>
  
  <pre><code>let screenEdgePanGesture = UIScreenEdgePanGestureRecognizer.init(target: self, action: #selector(self.didPanningScreen))
  screenEdgePanGesture.edges = .right
  screenEdgePanGesture.delegate = self
  self.view.addGestureRecognizer(screenEdgePanGesture)
  </code></pre>