IOS-69: close presented web view on the menu, when leaving the app, so that we…

IOS-69: close presented web view on the menu, when leaving the app, so that we didn't leave a blank screen in case of redirect to the AppStore.

1Weather/UI/View controllers/Menu/MenuViewController.swift

@@ -22,6 +22,20 @@ class MenuViewController: UIViewController {
         self.menuCellFactory = MenuCellFactory(viewModel: menuViewModel)
         super.init(nibName: nil, bundle: nil)
         self.viewModel.delegate = self
+        if #available(iOS 13.0, *) {
+            NotificationCenter.default.addObserver(self, selector: #selector(appWillEnterBackgroundHandler), name: UIScene.willDeactivateNotification, object: nil)
+        } else {
+            NotificationCenter.default.addObserver(self, selector: #selector(appWillEnterBackgroundHandler), name: UIApplication.willResignActiveNotification, object: nil)
+        }
+    }
+    
+    @objc
+    private func appWillEnterBackgroundHandler() {
+        self.presentedViewController?.dismiss(animated: false, completion: nil)
+    }
+    
+    deinit {
+        NotificationCenter.default.removeObserver(self)
     }
     
     required init?(coder: NSCoder) {