state: propogate error from state store (#8171)

* state: propogate error from state store

* fix lint

internal/state/errors.go

@@ -39,6 +39,7 @@ type (
 
 	ErrNoValSetForHeight struct {
 		Height int64
+		Err    error
 	}
 
 	ErrNoConsensusParamsForHeight struct {
@@ -89,9 +90,14 @@ func (e ErrStateMismatch) Error() string {
 }
 
 func (e ErrNoValSetForHeight) Error() string {
-	return fmt.Sprintf("could not find validator set for height #%d", e.Height)
+	if e.Err == nil {
+		return fmt.Sprintf("could not find validator set for height #%d", e.Height)
+	}
+	return fmt.Sprintf("could not find validator set for height #%d: %s", e.Height, e.Err.Error())
 }
 
+func (e ErrNoValSetForHeight) Unwrap() error { return e.Err }
+
 func (e ErrNoConsensusParamsForHeight) Error() string {
 	return fmt.Sprintf("could not find consensus params for height #%d", e.Height)
 }

internal/state/store.go

@@ -488,7 +488,7 @@ func (store dbStore) LoadValidators(height int64) (*types.ValidatorSet, error) {
 
 	valInfo, err := loadValidatorsInfo(store.db, height)
 	if err != nil {
-		return nil, ErrNoValSetForHeight{height}
+		return nil, ErrNoValSetForHeight{Height: height, Err: err}
 	}
 	if valInfo.ValidatorSet == nil {
 		lastStoredHeight := lastStoredHeightFor(height, valInfo.LastHeightChanged)