f8781364d2
- Refactor _run_mpp so that it takes only one set of arguments. Success and failure conditions are now tested by calling _run_mpp multiple times. - In test_payment_multipart with_timeout, check that the received failure message actually is MPP_TIMEOUT, and not a generic failure. Since the onion is obfuscated by the forwarding node, this tests that obfuscate_onion_packet and decode_onion_packet work as expected.