Fix: `gerrit review` with --message does not work with no labels

If `gerrit review` is called with the --message option and there
are no review labels given, the message is not added on the change.

This bug was introduced as a side-effect of commit a65b695e, which
intended to prevent the same message being added twice when the
--abandon and --restore options are used.

Commit a65b695e removes the review message if there are no labels,
but this is not quite correct.  The message should only be removed
if there are no labels _and_ the --abandon or --restore option is
used.

Update the condition accordingly.

Bug: issue 1874
Change-Id: I062a557b0ea251af826d16cc48a431ea5047ceb1
1 file changed