Remove HeaderBackend requirement from AuthorityDiscovery and NetworkWorker (#13730)

* Remove `HeaderBackend` requirement from `NetworkWorker`

* Remove HeaderBackend from authority-discovery

substrate/client/network/src/config.rs

@@ -34,6 +34,7 @@ use prometheus_endpoint::Registry;
 pub use sc_network_common::{role::Role, sync::warp::WarpSyncProvider, ExHashT};
 use zeroize::Zeroize;
 
+use sp_runtime::traits::Block as BlockT;
 use std::{
 	error::Error,
 	fmt, fs,
@@ -44,7 +45,6 @@ use std::{
 	path::{Path, PathBuf},
 	pin::Pin,
 	str::{self, FromStr},
-	sync::Arc,
 };
 
 pub use libp2p::{
@@ -688,7 +688,7 @@ impl NetworkConfiguration {
 }
 
 /// Network initialization parameters.
-pub struct Params<Client> {
+pub struct Params<Block: BlockT> {
 	/// Assigned role for our node (full, light, ...).
 	pub role: Role,
 
@@ -698,12 +698,12 @@ pub struct Params<Client> {
 	/// Network layer configuration.
 	pub network_config: NetworkConfiguration,
 
-	/// Client that contains the blockchain.
-	pub chain: Arc<Client>,
-
 	/// Legacy name of the protocol to use on the wire. Should be different for each chain.
 	pub protocol_id: ProtocolId,
 
+	/// Genesis hash of the chain
+	pub genesis_hash: Block::Hash,
+
 	/// Fork ID to distinguish protocols of different hard forks. Part of the standard protocol
 	/// name on the wire.
 	pub fork_id: Option<String>,