devtest -c with --offline and specific DIB_REPOREF_<project>'s fails if cache is older than refs

Looking at diskimage-builder/elements/source-repositories/extra-data.d/98-source-repositories the problematic section seems to be

               HAS_REF=$(git --git-dir=$CACHE_PATH/.git name-rev $REPOREF 2>/dev/null || true)
                if [ -z "$DIB_OFFLINE" -o -z "$HAS_REF" ] ; then
                    echo "Updating cache of $REPOLOCATION in $CACHE_PATH with ref $REPOREF"
                    git --git-dir=$CACHE_PATH/.git fetch --update-head-ok $REPOLOCATION ${REPOREF}:${REPOREF}
                fi

changing

                    git --git-dir=$CACHE_PATH/.git fetch --update-head-ok $REPOLOCATION ${REPOREF}:${REPOREF}
to
                    git --git-dir=$CACHE_PATH/.git fetch --update-head-ok $REPOLOCATION

eliminates this error - while this may make the fetch more extensive, and slightly slower, given its only updating cached repos and the other approach results in errors, I think the fix is preferable

That fix will work for sha1's, but will not work for master.

Looking to see what we can do to resolve that and solve for both use-cases.

A general solution may be to fetch all of the remote branches and make them local branches, as follows:

git --git-dir=$CACHE_PATH/.git fetch --update-head-ok $REPOLOCATION +refs/heads/*:refs/heads/*

This is the fix I will propose.

The general solution fails for gerrit, which is a key use case for this - I've opened a new bug about the regression.

This seems like it is probably no longer relevant.

This bug is > 365 days without activity. We are unsetting assignee and milestone and setting status to Incomplete in order to allow its expiry in 60 days.

If the bug is still valid, then update the bug status.

[Expired for tripleo because there has been no activity for 60 days.]