#560 take two, now that #560 has been reverted (#561)

* Clear upons upon round, not block

* Cache the proposal for a round

* Rebase onto develop, which reverted this PR, and re-apply this PR

* Set participation upon participation instead of constantly recalculating

* Cache message instances

* Add missing txn commit

Identified by @akildemir.

* Correct clippy lint identified upon rebase

* Fix tendermint chain sync (#581)

* fix p2p Reqres protocol

* stabilize tributary chain sync

* fix pr comments

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Co-authored-by: akildemir <34187742+akildemir@users.noreply.github.com>

common/db/src/parity_db.rs

@@ -4,6 +4,7 @@ pub use ::parity_db::{Options, Db as ParityDb};
 
 use crate::*;
 
+#[must_use]
 pub struct Transaction<'a>(&'a Arc<ParityDb>, Vec<(u8, Vec<u8>, Option<Vec<u8>>)>);
 
 impl Get for Transaction<'_> {

common/db/src/rocks.rs

@@ -7,6 +7,7 @@ use rocksdb::{
 
 use crate::*;
 
+#[must_use]
 pub struct Transaction<'a, T: ThreadMode>(
   RocksTransaction<'a, OptimisticTransactionDB<T>>,
   &'a OptimisticTransactionDB<T>,