fix InvalidateBlock to repopulate setBlockIndexCandidates
fix InvalidateBlock to repopulate setBlockIndexCandidates

Rebased-From: a9af415887f03cb2565895bc55be72748549e527
Github-Pull: #5879
(cherry picked from commit c91c660e499ff8f92130a349226fb3200823a82d)

reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin