gossipd: unify is_chan_public / is_chan_announced.

We used to have a `struct chan` while we're waiting for an update; now we
keep that internally.  So a `struct chan` without a channel_announcement
in the store is private, and other is public.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

gossipd/gossipd.c

@@ -1109,7 +1109,7 @@ static void maybe_create_next_scid_reply(struct peer *peer)
 		struct chan *chan;
 
 		chan = get_channel(rstate, &peer->scid_queries[i]);
-		if (!chan || !is_chan_announced(chan))
+		if (!chan || !is_chan_public(chan))
 			continue;
 
 		queue_peer_msg(peer, chan->channel_announce);

gossipd/routing.c

@@ -307,7 +307,7 @@ static bool node_announce_predates_channels(const struct node *node)
 	struct chan *c;
 
 	for (c = first_chan(node, &i); c; c = next_chan(node, &i)) {
-		if (!is_chan_announced(c))
+		if (!is_chan_public(c))
 			continue;
 
 		if (c->bcast.index < node->bcast.index)

gossipd/routing.h

@@ -64,15 +64,9 @@ struct chan {
 	struct amount_sat sat;
 };
 
-/* A local channel can exist which isn't announcable. */
+/* A local channel can exist which isn't announced; normal channels are only
+ * created once we have both an announcement *and* an update. */
 static inline bool is_chan_public(const struct chan *chan)
-{
-	return chan->channel_announce != NULL;
-}
-
-/* A channel is only announced once we have a channel_update to send
- * with it. */
-static inline bool is_chan_announced(const struct chan *chan)
 {
 	return chan->bcast.index != 0;
 }