Clean up the networking layer (#881)

substrate/node/network/src/consensus.rs

@@ -284,18 +284,10 @@ impl<P: AuthoringApi + Send + Sync + 'static> Network for ConsensusNetwork<P> {
 			}
 		});
 
-		match process_task {
-			Some(task) =>
-				if let Err(e) = Executor::spawn(&mut task_executor, Box::new(task)) {
-					debug!(target: "node-network", "Cannot spawn message processing: {:?}", e)
-				},
-			None => warn!(target: "node-network", "Cannot process incoming messages: network appears to be down"),
+		if let Err(e) = Executor::spawn(&mut task_executor, Box::new(process_task)) {
+			debug!(target: "node-network", "Cannot spawn message processing: {:?}", e)
 		}
 
 		(InputAdapter { input: bft_recv }, sink)
 	}
 }
-
-/// Error when the network appears to be down.
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct NetworkDown;