[CFT] Can I get some Tested-By's on this series?

Will people please test these patches with their container project?

These changes break container userspace (hopefully in a minimal way) if
I could have that confirmed by testing I would really appreciate it.  I
really don't want to send out a bug fix that accidentally breaks
userspace again.

The only issue sort of under discussion is if there is a better name for
/proc/<pid>/setgroups, and the name of the file will not affect the
functionality of the patchset.

With the code reviewed and written in simple obviously correct, easily
reviewable ways I am hoping/planning to send this to Linus ASAP.

Eric