check for existing login on FBLogin button render
check for existing login on FBLogin button render

brysgo/react-native-facebook-login,brysgo/react-native-facebook-login,lwhiteley/react-native-facebook-login,leonacky/react-native-facebook-login,brysgo/react-native-facebook-login,leonacky/react-native-facebook-login,lwhiteley/react-native-facebook-login,lwhiteley/react-native-facebook-login,leonacky/react-native-facebook-login