title: Popover in the navigation bar results in broken animation
body: <p>When I have a <code>popover</code> in the navigation bar the animation is broken when closing the <code>popover</code>. Also it can only be opened once. It works fine on the iPad, but the animation is different on the iPad. Is this a bug?</p>
  
  <pre class="lang-swift prettyprint-override"><code>struct ContentView: View {
      @State var showPopover:Bool = false
  
      var body: some View {
          NavigationView{
              Text("Popover Animation Test")
              .navigationBarItems(trailing: Button("Popover") { self.showPopover = true }
              .popover(isPresented: self.$showPopover) { Text("Hello from Popover") })
          }
      }
  }
  
  </code></pre>