Merge pull request #724 from OneSignal/fix/fix_scene_notif_names

Making scene notification names strings for Xcode 10 compilation

Author: emawby

iOS_SDK/OneSignalSDK/Source/OneSignalLifecycleObserver.m

@@ -60,9 +60,9 @@ + (void)registerLifecycleObserver {
 + (void)registerLifecycleObserverAsUIScene {
     if (@available(iOS 13.0, *)) {
         [OneSignal onesignal_Log:ONE_S_LL_VERBOSE message:@"registering for Scene Lifecycle notifications"];
-        [[NSNotificationCenter defaultCenter] addObserver:[OneSignalLifecycleObserver sharedInstance] selector:@selector(didEnterBackground) name:UISceneDidEnterBackgroundNotification object:nil];
-        [[NSNotificationCenter defaultCenter] addObserver:[OneSignalLifecycleObserver sharedInstance] selector:@selector(didBecomeActive) name:UISceneDidActivateNotification object:nil];
-        [[NSNotificationCenter defaultCenter] addObserver:[OneSignalLifecycleObserver sharedInstance] selector:@selector(willResignActive) name:UISceneWillDeactivateNotification object:nil];
+        [[NSNotificationCenter defaultCenter] addObserver:[OneSignalLifecycleObserver sharedInstance] selector:@selector(didEnterBackground) name:@"UISceneDidEnterBackgroundNotification" object:nil];
+        [[NSNotificationCenter defaultCenter] addObserver:[OneSignalLifecycleObserver sharedInstance] selector:@selector(didBecomeActive) name:@"UISceneDidActivateNotification" object:nil];
+        [[NSNotificationCenter defaultCenter] addObserver:[OneSignalLifecycleObserver sharedInstance] selector:@selector(willResignActive) name:@"UISceneWillDeactivateNotification" object:nil];
     }
 }