lnd: provide aux closer to chain arbitrator

The final step is to provide the aux closer to the corresponding configs
from the server. Here we use an adapter pattern which returns an aux
chan closer as defined in the contractcourt package.

Author: GeorgeTsagk

server.go

@@ -60,6 +60,7 @@ import (
 	"github.com/lightningnetwork/lnd/lnutils"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
+	chcl "github.com/lightningnetwork/lnd/lnwallet/chancloser"
 	"github.com/lightningnetwork/lnd/lnwallet/chanfunding"
 	"github.com/lightningnetwork/lnd/lnwallet/rpcwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
@@ -1375,6 +1376,11 @@ func newServer(ctx context.Context, cfg *Config, listenAddrs []net.Addr,
 		AuxLeafStore: implCfg.AuxLeafStore,
 		AuxSigner:    implCfg.AuxSigner,
 		AuxResolver:  implCfg.AuxContractResolver,
+		AuxCloser: fn.MapOption(
+			func(c chcl.AuxChanCloser) contractcourt.AuxChanCloser {
+				return c
+			},
+		)(implCfg.AuxChanCloser),
 	}, dbs.ChanStateDB)
 
 	// Select the configuration and funding parameters for Bitcoin.