largefiles: don't crash when cloning to a remote repo
The immediate crash was when checking for requirements immediately after this,
but lfcommands.downloadlfiles() will also crash if --all-largefiles is
specified. That has been in place since atleast
5884812686f7 (2.3-rc) without
anyone noticing.
I can't tell from the peer classes if there's a way to make the custom largefile
functionality work in this case, but atleast it doesn't crash.
$ hg init
$ touch unknown
$ touch a
$ hg add a
$ hg ci -m "1"
$ touch b
$ hg add b
$ hg ci -m "2"
Should show unknown
$ hg status
? unknown
$ hg revert -r 0 --all
removing b
Should show unknown and b removed
$ hg status
R b
? unknown
Should show a and unknown
$ ls
a
unknown