htlcswitch/test: use real invoice registry with temp db as mock

In further commits the behaviour of invoice registry becomes more
intrinsically connected to the link. This commit prepares for that by
allowing link and registry to be tested as a single unit.

htlcswitch/link_test.go

@@ -2046,7 +2046,9 @@ func TestChannelLinkBandwidthConsistency(t *testing.T) {
 
 	// We must add the invoice to the registry, such that Alice expects
 	// this payment.
-	err = coreLink.cfg.Registry.(*mockInvoiceRegistry).AddInvoice(*invoice)
+	err = coreLink.cfg.Registry.(*mockInvoiceRegistry).AddInvoice(
+		*invoice, htlc.PaymentHash,
+	)
 	if err != nil {
 		t.Fatalf("unable to add invoice to registry: %v", err)
 	}
@@ -2148,7 +2150,9 @@ func TestChannelLinkBandwidthConsistency(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unable to create payment: %v", err)
 	}
-	err = coreLink.cfg.Registry.(*mockInvoiceRegistry).AddInvoice(*invoice)
+	err = coreLink.cfg.Registry.(*mockInvoiceRegistry).AddInvoice(
+		*invoice, htlc.PaymentHash,
+	)
 	if err != nil {
 		t.Fatalf("unable to add invoice to registry: %v", err)
 	}
@@ -3804,7 +3808,9 @@ func TestChannelLinkAcceptDuplicatePayment(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if err := n.carolServer.registry.AddInvoice(*invoice); err != nil {
+
+	err = n.carolServer.registry.AddInvoice(*invoice, htlc.PaymentHash)
+	if err != nil {
 		t.Fatalf("unable to add invoice in carol registry: %v", err)
 	}
 
@@ -4182,7 +4188,8 @@ func generateHtlc(t *testing.T, coreLink *channelLink,
 	// We must add the invoice to the registry, such that Alice
 	// expects this payment.
 	err := coreLink.cfg.Registry.(*mockInvoiceRegistry).AddInvoice(
-		*invoice)
+		*invoice, htlc.PaymentHash,
+	)
 	if err != nil {
 		t.Fatalf("unable to add invoice to registry: %v", err)
 	}