zpay32: rename to DefaultAssumedFinalCLTVDelta

This renames the paramter to clarify that this value is only used when
no CLTV value was decoded from the payment request

zpay32/hophint.go

@@ -3,9 +3,10 @@ package zpay32
 import "github.com/btcsuite/btcd/btcec"
 
 const (
-	// DefaultFinalCLTVDelta is the default value to be used as the final
-	// CLTV delta for a route if one is unspecified.
-	DefaultFinalCLTVDelta = 9
+	// DefaultAssumedFinalCLTVDelta is the default value to be used as the
+	// final CLTV delta for a route if one is unspecified in the payment
+	// request.
+	DefaultAssumedFinalCLTVDelta = 9
 )
 
 // HopHint is a routing hint that contains the minimum information of a channel

zpay32/invoice.go

@@ -324,7 +324,7 @@ func (invoice *Invoice) MinFinalCLTVExpiry() uint64 {
 		return *invoice.minFinalCLTVExpiry
 	}
 
-	return DefaultFinalCLTVDelta
+	return DefaultAssumedFinalCLTVDelta
 }
 
 // validateInvoice does a sanity check of the provided Invoice, making sure it