More tests fixed.

substrate/polkadot-primitives/src/block.rs

@@ -168,7 +168,6 @@ mod tests {
 	use super::*;
 	use codec::Slicable;
 	use substrate_serializer as ser;
-	use primitives::hexdisplay::HexDisplay;
 
 	#[test]
 	fn test_header_serialization() {

substrate/polkadot-primitives/src/transaction.rs

@@ -286,10 +286,6 @@ pub struct Transaction {
 
 impl Slicable for Transaction {
 	fn from_slice(value: &mut &[u8]) -> Option<Self> {
-		// This is a little more complicated than usua since the binary format must be compatible
-		// with substrate's generic `Vec<u8>` type. Basically this just means accepting that there
-		// will be a prefix of u32, which has the total number of bytes following (we don't need
-		// to use this).
 		Some(Transaction {
 			signed: try_opt!(Slicable::from_slice(value)),
 			nonce: try_opt!(Slicable::from_slice(value)),