`upgrade` will fail and leave the repo broken when run in a
v5 direct repo with annex.alwayscommit=false and not synced since the last
change.

> Forwarded from a private email to me, have not reproduced yet. --[[Joey]]

Update: Got a repo tarball sent to me that reproduces the problem. It looks like
this:

	git annex upgrade
	upgrade (v5 to v6...) 
	  caught exception: Somehow no branch is checked out
	<callstack>
	failed
	(recording state in git...)
	git-annex: upgrade: 1 failed

.git/HEAD points to refs/heads/annex/direct/master, 
but that ref does not actually exist yet.

The repo was created with git-annex 7.20190731-gbb16a2610
and this sequence of commands:

	git init .

	git config user.email "email@example.com"
	git config user.name "Name Name"
	git config annex.alwayscommit false
	git config annex.autoupgraderepository false
	git annex init foobar
	git annex direct
	echo "aaaa" > a && echo "bbbb" > b
	git annex add a b
	git annex drop --force a

Note that lack of git-annex sync, which is why the branch
never got created. The index file has the adds staged of course.

> [[fixed|done]] --[[Joey]]
