rebase --apply: fix reflog

move_to_original_branch() passes the message intended for the branch
reflog as `orig_head_msg`. Fix this by adding a `branch_msg` member to
struct reset_head_opts and add a regression test.  Note that these
reflog messages do not respect GIT_REFLOG_ACTION. They are not alone
in that and will be fixed in a future series.

The "merge" backend already has tests that check both the branch and
HEAD reflogs.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/reset.h b/reset.h
index a205be2..7ef7e43 100644
--- a/reset.h
+++ b/reset.h
@@ -31,6 +31,10 @@ struct reset_head_opts {
 	 */
 	unsigned flags;
 	/*
+	 * Optional reflog message for branch, defaults to head_msg.
+	 */
+	const char *branch_msg;
+	/*
 	 * Optional reflog message for HEAD, if this omitted but oid or branch
 	 * are given then default_reflog_action must be given.
 	 */