multi: set the InboundFee on ChannelEdgePolicy

In this commit, we make sure to set the new field wherever appropriate.
This will be any place where the ChannelEdgePolicy is constructed other
than its disk deserialisation.

routing/localchans/manager.go

@@ -127,12 +127,10 @@ func (r *Manager) UpdatePolicy(newSchema routing.ChannelPolicy,
 			Edge: edge,
 		})
 
-		// Extract inbound fees from the ExtraOpaqueData.
 		var inboundWireFee lnwire.Fee
-		_, err = edge.ExtraOpaqueData.ExtractRecords(&inboundWireFee)
-		if err != nil {
-			return err
-		}
+		edge.InboundFee.WhenSome(func(fee lnwire.Fee) {
+			inboundWireFee = fee
+		})
 		inboundFee := models.NewInboundFeeFromWire(inboundWireFee)
 
 		// Add updated policy to list of policies to send to switch.
@@ -372,6 +370,8 @@ func (r *Manager) updateEdge(chanPoint wire.OutPoint,
 	err = fn.MapOptionZ(newSchema.InboundFee,
 		func(f models.InboundFee) error {
 			inboundWireFee := f.ToWire()
+			edge.InboundFee = fn.Some(inboundWireFee)
+
 			return edge.ExtraOpaqueData.PackRecords(
 				&inboundWireFee,
 			)