Summary: Currently we don't have a flag in iOS setup which lets us know if the code is going to be compiled in Open source or internally. Till now we didn't have a use case for it. But NT team is hacking a componentkit descriptor which is open sourced. This flag will come in handy for us to keep the open source setup build successfully.
Reviewed By: jknoxville
Differential Revision: D10854300
fbshipit-source-id: ac5da6f239b2066b6d7f0680cbfc1b7062ae0f36