[Raft] Pending logs events no longer being handled

[chris-j-h]

System information

Current master branch

 ~/Work/quorum-examples/examples/7nodes % geth version
Geth
Version: 1.9.20-stable
Git Commit: eb8f6bf522629bac2eba2e39474fa169753ca712
Git Commit Date: 20210326
Quorum Version: 21.1.0

Issue

#1121 introduced ethereum/go-ethereum#20312 which switches from event.TypeMux to an event.Feed subscription for sending pending logs events to the filters package.

raft.minter::firePendingBlockEvents still sends these events on the event.TypeMux and as a result the filters package is not handling them.

Steps to reproduce the behaviour

This can be observed by subscribing to logs events on a websockets-enabled leader node using something like wscat, e.g.:

~/Work/quorum-examples/examples/7nodes % wscat -c ws://localhost:23004
Connected (press CTRL+C to quit)

> {"id":1, "method":"eth_subscribe", "params":["logs", {"FromBlock":"pending","ToBlock":"pending"}]}

When sending transactions that emit logs, no events are returned by the subscription.