Merge branch 'jc/sequencer-stopped-sha-simplify'

Recently the format of an internal state file "rebase -i" uses has
been tightened up for consistency, which would hurt those who start
"rebase -i" with old git and then continue with new git.  Loosen
the reader side a bit (which we may want to tighten again in a year
or so).

* jc/sequencer-stopped-sha-simplify:
  sequencer: tolerate abbreviated stopped-sha file

Author: gitster

sequencer.c

@@ -2651,7 +2651,7 @@ static int read_populate_opts(struct replay_opts *opts)
 		}
 
 		if (read_oneliner(&buf, rebase_path_squash_onto(), 0)) {
-			if (get_oid_hex(buf.buf, &opts->squash_onto) < 0) {
+			if (get_oid_committish(buf.buf, &opts->squash_onto) < 0) {
 				ret = error(_("unusable squash-onto"));
 				goto done_rebase_i;
 			}