Move inner code to poll_and_update_listeners_inner

Previously, we might have overlooked some cases that would exit the
method and bubble up an error via `?` instead of propagating to all subscribers.
Here, we split out the code to an inner method to ensure we always
propagate.

Author: tnull

src/chain/bitcoind.rs

@@ -306,6 +306,18 @@ impl BitcoindChainSource {
 			})?;
 		}
 
+		let res = self
+			.poll_and_update_listeners_inner(channel_manager, chain_monitor, output_sweeper)
+			.await;
+
+		self.wallet_polling_status.lock().unwrap().propagate_result_to_subscribers(res);
+		res
+	}
+
+	async fn poll_and_update_listeners_inner(
+		&self, channel_manager: Arc<ChannelManager>, chain_monitor: Arc<ChainMonitor>,
+		output_sweeper: Arc<Sweeper>,
+	) -> Result<(), Error> {
 		let latest_chain_tip_opt = self.latest_chain_tip.read().unwrap().clone();
 		let chain_tip = if let Some(tip) = latest_chain_tip_opt {
 			tip
@@ -403,9 +415,7 @@ impl BitcoindChainSource {
 			},
 		}
 
-		let res = Ok(());
-		self.wallet_polling_status.lock().unwrap().propagate_result_to_subscribers(res);
-		res
+		Ok(())
 	}
 
 	pub(super) async fn update_fee_rate_estimates(&self) -> Result<(), Error> {