Revert "Removed unused UIWindow properties from AppDelegate from the Swift apps"

This reverts commit c5dd6e7.

Author: Rad Azzouz

Demos/App Demo for iOS Swift/App Demo for iOS Swift/AppDelegate.swift

@@ -10,7 +10,9 @@ import UIKit
 
 @UIApplicationMain
 class AppDelegate: UIResponder, UIApplicationDelegate {
-	
+
+	var window: UIWindow?
+
 	func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
 		// Override point for customization after application launch.
 		return true

Demos/WebView Demo for iOS Swift/WebView Demo for iOS Swift/AppDelegate.swift

@@ -11,6 +11,8 @@ import UIKit
 @UIApplicationMain
 class AppDelegate: UIResponder, UIApplicationDelegate {
 
+	var window: UIWindow?
+
 	func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
 		// Override point for customization after application launch.
 		return true