"git rebase" that has recently been rewritten in C had a few issues
in its "--autstash" feature, which have been corrected.
* js/rebase-autostash-fix:
rebase --autostash: fix issue with dirty submodules
rebase --autostash: demonstrate a problem with dirty submodules
rebase (autostash): use an explicit OID to apply the stash
rebase (autostash): store the full OID in <state-dir>/autostash
rebase (autostash): avoid duplicate call to state_dir_path()