Use initWithFrame: to create the in-app message window in non-UIScene apps (#7080)

* If the app doesn't have a scene delegate, use initWithFrame: to create the in-app message window

* Refactor window creation method for iOS 13 and above

* Add CHANGELOG entry

* Fix CHANGELOG entry

Author: christibbs

FirebaseInAppMessaging/CHANGELOG.md

@@ -1,3 +1,6 @@
+# 2020-12 -- v7.3.0
+- [fixed] Fixed default display bug in apps that don't use `UISceneDelegate` (#6803).
+
 # 2020-10 -- v7.0.0
 - [removed] Removed deprecated elements of in-app messaging API.
 

FirebaseInAppMessaging/Sources/DefaultUI/FIRIAMRenderingWindowHelper.m

@@ -29,8 +29,7 @@ + (UIWindow *)UIWindowForModalView {
   dispatch_once(&onceToken, ^{
 #if defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 130000
     if (@available(iOS 13.0, *)) {
-      UIWindowScene *foregroundedScene = [[self class] foregroundedScene];
-      UIWindowForModal = [[UIWindow alloc] initWithWindowScene:foregroundedScene];
+      UIWindowForModal = [[self class] iOS13PlusWindow];
     } else {
 #endif  // defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 130000
       UIWindowForModal = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
@@ -49,8 +48,7 @@ + (UIWindow *)UIWindowForBannerView {
   dispatch_once(&onceToken, ^{
 #if defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 130000
     if (@available(iOS 13.0, *)) {
-      UIWindowScene *foregroundedScene = [[self class] foregroundedScene];
-      UIWindowForBanner = [[FIRIAMBannerViewUIWindow alloc] initWithWindowScene:foregroundedScene];
+      UIWindowForBanner = [[self class] iOS13PlusBannerWindow];
     } else {
 #endif  // defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 130000
       UIWindowForBanner =
@@ -71,8 +69,7 @@ + (UIWindow *)UIWindowForImageOnlyView {
   dispatch_once(&onceToken, ^{
 #if defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 130000
     if (@available(iOS 13.0, *)) {
-      UIWindowScene *foregroundedScene = [[self class] foregroundedScene];
-      UIWindowForImageOnly = [[UIWindow alloc] initWithWindowScene:foregroundedScene];
+      UIWindowForImageOnly = [[self class] iOS13PlusWindow];
     } else {
 #endif  // defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= 130000
       UIWindowForImageOnly = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
@@ -94,6 +91,25 @@ + (UIWindowScene *)foregroundedScene API_AVAILABLE(ios(13.0)) {
   }
   return nil;
 }
+
++ (UIWindow *)iOS13PlusWindow API_AVAILABLE(ios(13.0)) {
+  UIWindowScene *foregroundedScene = [[self class] foregroundedScene];
+  if (foregroundedScene.delegate) {
+    return [[UIWindow alloc] initWithWindowScene:foregroundedScene];
+  } else {
+    return [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
+  }
+}
+
++ (FIRIAMBannerViewUIWindow *)iOS13PlusBannerWindow API_AVAILABLE(ios(13.0)) {
+  UIWindowScene *foregroundedScene = [[self class] foregroundedScene];
+  if (foregroundedScene.delegate) {
+    return [[FIRIAMBannerViewUIWindow alloc] initWithWindowScene:foregroundedScene];
+  } else {
+    return [[FIRIAMBannerViewUIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
+  }
+}
+
 #endif
 @end