Launching a watchOS extension on device with the managed debugger
attached is slow, which means that the launch watchdog will kick in
and kill the app before it has launched.
So we attach the native debugger as well, which prevents the launch
watchdog from killing the app. Incidentally it also makes watchOS
not background the app.
We're using private API to determine whether a native debugger is
attached, but it's only in debug code, and as such would not be
included in release builds for customer apps. Also the code is
currently limited to watchOS since it's not needed on other
platforms for now.
Rolf Bjarne Kvinge