Make sure to preserve backing votes (#6382)

* Guide updates

* Consider more dead forks.

* Ensure backing votes don't get overridden.

* Fix spelling.

* Fix comments.

* Update node/primitives/src/lib.rs

Co-authored-by: Tsvetomir Dimitrov <tsvetomir@parity.io>

Co-authored-by: eskimor <eskimor@no-such-url.com>
Co-authored-by: Tsvetomir Dimitrov <tsvetomir@parity.io>

polkadot/node/core/provisioner/src/disputes/prioritized_selection/mod.rs

@@ -216,7 +216,7 @@ where
 
 		// Check if votes are within the limit
 		for (session_index, candidate_hash, selected_votes) in votes {
-			let votes_len = selected_votes.valid.len() + selected_votes.invalid.len();
+			let votes_len = selected_votes.valid.raw().len() + selected_votes.invalid.len();
 			if votes_len + total_votes_len > MAX_DISPUTE_VOTES_FORWARDED_TO_RUNTIME {
 				// we are done - no more votes can be added
 				return result

polkadot/node/core/provisioner/src/disputes/prioritized_selection/tests.rs

@@ -393,7 +393,9 @@ impl TestDisputes {
 					ValidDisputeStatementKind::Explicit,
 					0,
 					local_votes_count,
-				),
+				)
+				.into_iter()
+				.collect(),
 				invalid: BTreeMap::new(),
 			},
 		);