Refactor DiscardFunding event to use only bitcoin transaction

Author: 1nF0rmed

lightning/src/util/events.rs

@@ -262,7 +262,7 @@ pub enum Event {
 		/// The channel_id of the channel which has been closed.
 		channel_id: [u8; 32],
 		/// The full transaction received from the user
-		transaction: Option<Transaction>
+		transaction: Transaction
 	}
 }
 
@@ -353,7 +353,7 @@ impl Writeable for Event {
 				11u8.write(writer)?;
 				write_tlv_fields!(writer, {
 					(0, channel_id, required),
-					(2, transaction, option)
+					(2, transaction, required)
 				})
 			},
 			// Note that, going forward, all new events must only write data inside of
@@ -489,12 +489,11 @@ impl MaybeReadable for Event {
 			},
 			11u8 => {
 				let mut channel_id = [0; 32];
-				let mut transaction = None;
+				let mut transaction = Transaction{ version: 2, lock_time: 0, input: Vec::new(), output: Vec::new() };
 				read_tlv_fields!(reader, {
 					(0, channel_id, required),
-					(2, transaction, ignorable),
+					(2, transaction, required),
 				});
-				if transaction.is_none() { return Ok(None); }
 				Ok(Some(Event::DiscardFunding { channel_id, transaction } ))
 			},
 			// Versions prior to 0.0.100 did not ignore odd types, instead returning InvalidValue.