_encode_varint_length_prefixed_tlv!(w, {
(2, HighZeroBytesDroppedBigSize(self.amt_to_forward), required),
(4, HighZeroBytesDroppedBigSize(self.outgoing_cltv_value), required),
(8, payment_data, option),
_encode_varint_length_prefixed_tlv!(w, {
(2, HighZeroBytesDroppedBigSize(self.amt_to_forward), required),
(4, HighZeroBytesDroppedBigSize(self.outgoing_cltv_value), required),
(8, payment_data, option),