Well, if Google does it then I guess I stand corrected about it being a weirdo way to deliver patches. They went so far as to .gz theirs, too, for extra non-browsing by mere mortals.
For Google it's undoubtedly only done because under the license agreement they must make their source code modifications available if someone asks. A form of malicious compliance if you wish
I find it curious that <https://github.com/google/mysql-tools/blob/02d18542735a528c4...> and yet <https://github.com/google/mysql-tools/blob/02d18542735a528c4...> says "diff -ruN base/client/mysqldump.c mysql40gpl/client/mysqldump.c"
I had no idea one could release patches of GPL software under an Apache license. That makes my head hurt.