multi: extract and pass through IsZombieChannel method

discovery/gossiper.go

@@ -335,6 +335,11 @@ type Config struct {
 	// to without iterating over the entire set of open channels.
 	FindChannel func(node *btcec.PublicKey, chanID lnwire.ChannelID) (
 		*channeldb.OpenChannel, error)
+
+	// IsStillZombieChannel takes the timestamps of the latest channel
+	// updates for a channel and returns true if the channel should be
+	// considered a zombie based on these timestamps.
+	IsStillZombieChannel func(time.Time, time.Time) bool
 }
 
 // processedNetworkMsg is a wrapper around networkMsg and a boolean. It is
@@ -519,6 +524,7 @@ func New(cfg Config, selfKeyDesc *keychain.KeyDescriptor) *AuthenticatedGossiper
 		IgnoreHistoricalFilters: cfg.IgnoreHistoricalFilters,
 		BestHeight:              gossiper.latestHeight,
 		PinnedSyncers:           cfg.PinnedSyncers,
+		IsStillZombieChannel:    cfg.IsStillZombieChannel,
 	})
 
 	gossiper.reliableSender = newReliableSender(&reliableSenderCfg{

discovery/sync_manager.go

@@ -102,6 +102,11 @@ type SyncManagerCfg struct {
 	// ActiveSync upon connection. These peers will never transition to
 	// PassiveSync.
 	PinnedSyncers PinnedSyncers
+
+	// IsStillZombieChannel takes the timestamps of the latest channel
+	// updates for a channel and returns true if the channel should be
+	// considered a zombie based on these timestamps.
+	IsStillZombieChannel func(time.Time, time.Time) bool
 }
 
 // SyncManager is a subsystem of the gossiper that manages the gossip syncers
@@ -501,6 +506,7 @@ func (m *SyncManager) createGossipSyncer(peer lnpeer.Peer) *GossipSyncer {
 		markGraphSynced:           m.markGraphSynced,
 		maxQueryChanRangeReplies:  maxQueryChanRangeReplies,
 		noTimestampQueryOption:    m.cfg.NoTimestampQueries,
+		isStillZombieChannel:      m.cfg.IsStillZombieChannel,
 	})
 
 	// Gossip syncers are initialized by default in a PassiveSync type

discovery/syncer.go

@@ -293,6 +293,11 @@ type gossipSyncerCfg struct {
 	// maxQueryChanRangeReplies is the maximum number of replies we'll allow
 	// for a single QueryChannelRange request.
 	maxQueryChanRangeReplies uint32
+
+	// isStillZombieChannel takes the timestamps of the latest channel
+	// updates for a channel and returns true if the channel should be
+	// considered a zombie based on these timestamps.
+	isStillZombieChannel func(time.Time, time.Time) bool
 }
 
 // GossipSyncer is a struct that handles synchronizing the channel graph state