Change LogDebug to NSLog in app's swizzling code. (#783)

* Change LogDebug to NSLog.

* Change log message.

* Add comment.

Author: jonsimantov

app/src/invites/ios/invites_ios_startup.mm

@@ -284,7 +284,8 @@ static void HookAppDelegateMethods(Class clazz) {
 // http://www.opensource.apple.com/source/objc4/objc4-274/runtime/objc-runtime.m)
 @implementation UIApplication (FIRFBI)
 + (void)load {
-  ::firebase::LogDebug("Loading UIApplication FIRFBI category");
+  // C++ constructors may not be called yet so call NSLog rather than LogDebug.
+  NSLog(@"Loading UIApplication category for Firebase App");
   ::firebase::util::ForEachAppDelegateClass(^(Class clazz) {
     ::firebase::invites::HookAppDelegateMethods(clazz);
   });

release_build_files/readme.md

@@ -567,6 +567,13 @@ workflow use only during the development of your app, not for publicly shipping
 code.
 
 ## Release Notes
+### Next Release
+-   Changes
+    -   General (iOS): Fixed an intermittent crash on iOS 15 caused by
+        constructing C++ objects during Objective-C's `+load` method.
+	([#706](https://github.com/firebase/firebase-cpp-sdk/pull/706))
+	([#783](https://github.com/firebase/firebase-cpp-sdk/pull/783))
+
 ### 8.8.0
 -   Changes
     -   General: Fixed a data race that could manifest as null pointer