Java has nulls, and any object reference in Java can be null, but in Kotlin parameters default to not null unless the type is specified as `Type?`; our override of onActivityResult was specifying the type of the intent parameter as `Intent` instead of `Intent?`, causing an exception before our code was called. Figuring out how to turn on "break on all exceptions" in Android Studio (which is non-trivial for some reason) finally showed me the stack trace.
