[viewchange] check quorum by mask

Signed-off-by: Leo Chen <leo@harmony.one>

consensus/quorum/one-node-staked-vote.go

@@ -146,6 +146,9 @@ func (v *stakedVoteWeight) IsQuorumAchieved(p Phase) bool {
 // IsQuorumAchivedByMask ..
 func (v *stakedVoteWeight) IsQuorumAchievedByMask(mask *bls_cosi.Mask) bool {
 	threshold := v.QuorumThreshold()
+	if mask == nil {
+		return false
+	}
 	currentTotalPower := v.computeTotalPowerByMask(mask)
 	if currentTotalPower == nil {
 		return false

consensus/view_change.go

@@ -351,7 +351,7 @@ func (consensus *Consensus) onViewChange(msg *msg_pb.Message) {
 		return
 	}
 
-	if consensus.Decider.IsQuorumAchieved(quorum.ViewChange) {
+	if consensus.Decider.IsQuorumAchievedByMask(consensus.vc.GetViewIDBitmap(recvMsg.ViewID)) {
 		consensus.getLogger().Info().
 			Int64("have", consensus.Decider.SignersCount(quorum.ViewChange)).
 			Int64("need", consensus.Decider.TwoThirdsSignersCount()).