dualfund: add switch for if the incoming channel is "too early"

If we get an error on a channel that doesn't have commitments yet,
we can just delete it.

lightningd/channel.c

@@ -886,6 +886,9 @@ void channel_fail_permanent(struct channel *channel,
 				  reason,
 				  why);
 
+	if (channel_state_open_uncommitted(channel->state))
+		delete_channel(channel);
+
 	tal_free(why);
 }
 

lightningd/channel.h

@@ -655,6 +655,31 @@ static inline bool channel_state_wants_onchain_fail(enum channel_state state)
 	abort();
 }
 
+static inline bool channel_state_open_uncommitted(enum channel_state state)
+{
+	switch (state) {
+	case DUALOPEND_OPEN_INIT:
+	case DUALOPEND_OPEN_COMMIT_READY:
+		return true;
+	case CLOSINGD_COMPLETE:
+	case AWAITING_UNILATERAL:
+	case FUNDING_SPEND_SEEN:
+	case ONCHAIN:
+	case CLOSED:
+	case CHANNELD_AWAITING_LOCKIN:
+	case DUALOPEND_OPEN_COMMITTED:
+	case DUALOPEND_AWAITING_LOCKIN:
+	case CHANNELD_NORMAL:
+	case CHANNELD_AWAITING_SPLICE:
+	case CLOSINGD_SIGEXCHANGE:
+	case CHANNELD_SHUTTING_DOWN:
+		return false;
+	}
+
+	abort();
+}
+
+
 void channel_set_owner(struct channel *channel, struct subd *owner);
 
 /* Channel has failed, but can try again.  Usually, set disconnect to true. */

lightningd/peer_control.c

@@ -375,6 +375,12 @@ void drop_to_chain(struct lightningd *ld, struct channel *channel,
 		log_broken(channel->log,
 			   "Cannot broadcast our commitment tx:"
 			   " they have a future one");
+	} else if (channel_state_open_uncommitted(channel->state)) {
+		/* There's no commitment transaction, we can
+		 * safely forget this channel */
+		log_info(channel->log,
+			 "Initialized channel (v2) received error"
+			 ", we're deleting the channel");
 	} else if (invalid_last_tx(channel->last_tx)) {
 		log_broken(channel->log,
 			   "Cannot broadcast our commitment tx:"