I was having this warning when submitting my app with Application Loader.
The app references non-public selector in MyApp : id
This warning
I solved this issue (where 13.1 would still generate warnings and produce an invalid binary in itunesconnect) by downloading the FacebookSDK source from Github (link) and using the "build_framework.sh" script in the scripts dir. Then added the generated framework to my Xcode project - and got no more warnings.