We should never be evicting channel_announcements because a) they were
deeply buried and should not change the short_channel_id/tag, b) they
are static.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
If channel_announce is rebroadcast, it should replace the existing one
in-place. We currently only do this if we start from the unsigned one
and replace it with the signed one when we hit 6 confirms.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
