Optimize: using parameters in func (#2845)

Signed-off-by: Zeyu Zhu <zhuzeyu0409@gmail.com>

state/store.go

@@ -96,7 +96,7 @@ func saveState(db dbm.DB, state State, key []byte) {
 	saveValidatorsInfo(db, nextHeight+1, state.LastHeightValidatorsChanged, state.NextValidators)
 	// Save next consensus params.
 	saveConsensusParamsInfo(db, nextHeight, state.LastHeightConsensusParamsChanged, state.ConsensusParams)
-	db.SetSync(stateKey, state.Bytes())
+	db.SetSync(key, state.Bytes())
 }
 
 //------------------------------------------------------------------------