Reported-by: Henri Beqi
As discussed with Christian, prepending the length to the payload returned is awkward, but it's the only way to set a legacy payload. As this will be soon deprecated, simplify the external API. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Changelog-added: `htlc_accepted` hook can now offer a replacement onion `payload`.