8f3fcdd1a8
1. In lnhtlc, sent_in_ctn and failed_in_ctn need to look at the remote ctx, and they need to be called when we receive a revocation, not when we send one. 2. In lnchannel, we use 3 lnworker callbacks: - payment sent/payment failed (called when we receive a revocation) - payment received (called when we send a revocation) 3. Make revoke_current_commitment return a single value. The second value was only used in tests, there is no need to bloat the code with that