If the upstream source tarball contains both fonts, you'll have to document both licenses in the copyright file anyway. Better to submit one source package named fonts-google-crosextra.
Once they're in the same source package, I doubt that there's any reason to put the fonts into separate binary packages either. Robert Ransom -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org