multi: use separate cltv expiry field from invoice

Now that the Invoice struct contains the decoded final cltv delta value,
the decoding of payment requests can be removed from the invoice
registry.

lnrpc/invoicesrpc/utils.go

@@ -36,13 +36,6 @@ func CreateRPCInvoice(invoice *channeldb.Invoice,
 		settleDate = invoice.SettleDate.Unix()
 	}
 
-	// Expiry time will default to 3600 seconds if not specified
-	// explicitly.
-	expiry := int64(decoded.Expiry().Seconds())
-
-	// The expiry will default to 9 blocks if not specified explicitly.
-	cltvExpiry := decoded.MinFinalCLTVExpiry()
-
 	// Convert between the `lnrpc` and `routing` types.
 	routeHints := CreateRPCRouteHints(decoded.RouteHints)
 
@@ -77,8 +70,8 @@ func CreateRPCInvoice(invoice *channeldb.Invoice,
 		Settled:         isSettled,
 		PaymentRequest:  paymentRequest,
 		DescriptionHash: descHash,
-		Expiry:          expiry,
-		CltvExpiry:      cltvExpiry,
+		Expiry:          int64(invoice.Expiry.Seconds()),
+		CltvExpiry:      uint64(invoice.FinalCltvDelta),
 		FallbackAddr:    fallbackAddr,
 		RouteHints:      routeHints,
 		AddIndex:        invoice.AddIndex,