Update parity-scale-codec to 2.0 (#7994)

* update cargo.toml

* use 2.0 in mmmr

substrate/client/network/src/protocol.rs

@@ -656,7 +656,7 @@ impl<B: BlockT, H: ExHashT> Protocol<B, H> {
 					"Couldn't decode packet sent by {}: {:?}: {}",
 					who,
 					data,
-					err.what(),
+					err,
 				);
 				self.peerset_handle.report_peer(who, rep::BAD_MESSAGE);
 				return CustomMessageOutcome::None;
@@ -1737,7 +1737,7 @@ impl<B: BlockT, H: ExHashT> NetworkBehaviour for Protocol<B, H> {
 										"Couldn't decode handshake sent by {}: {:?}: {} & {}",
 										peer_id,
 										received_handshake,
-										err.what(),
+										err,
 										err2,
 									);
 									self.peerset_handle.report_peer(peer_id, rep::BAD_MESSAGE);

substrate/client/network/src/protocol/message.rs

@@ -95,7 +95,7 @@ impl BlockAttributes {
 }
 
 impl Encode for BlockAttributes {
-	fn encode_to<T: Output>(&self, dest: &mut T) {
+	fn encode_to<T: Output + ?Sized>(&self, dest: &mut T) {
 		dest.push_byte(self.bits())
 	}
 }
@@ -198,7 +198,7 @@ pub mod generic {
 	}
 
 	impl codec::Encode for Roles {
-		fn encode_to<T: codec::Output>(&self, dest: &mut T) {
+		fn encode_to<T: codec::Output + ?Sized>(&self, dest: &mut T) {
 			dest.push_byte(self.bits())
 		}
 	}
@@ -282,7 +282,7 @@ pub mod generic {
 		/// Batch of consensus protocol messages.
 		// NOTE: index is incremented by 2 due to finality proof related
 		// messages that were removed.
-		#[codec(index = "17")]
+		#[codec(index = 17)]
 		ConsensusBatch(Vec<ConsensusMessage>),
 	}
 
@@ -402,7 +402,7 @@ pub mod generic {
 	// This assumes that the packet contains nothing but the announcement message.
 	// TODO: Get rid of it once protocol v4 is common.
 	impl<H: Encode> Encode for BlockAnnounce<H> {
-		fn encode_to<T: Output>(&self, dest: &mut T) {
+		fn encode_to<T: Output + ?Sized>(&self, dest: &mut T) {
 			self.header.encode_to(dest);
 			if let Some(state) = &self.state {
 				state.encode_to(dest);