Bump iavl version (#489)

go.mod

@@ -13,7 +13,7 @@ require (
 	github.com/cosmos/btcutil v1.0.4
 	github.com/cosmos/go-bip39 v1.0.0
 	github.com/cosmos/gogoproto v1.4.11
-	github.com/cosmos/iavl v0.19.4
+	github.com/cosmos/iavl v0.19.7
 	github.com/cosmos/ledger-cosmos-go v0.11.1
 	github.com/gogo/gateway v1.1.0
 	github.com/gogo/protobuf v1.3.3

go.sum

@@ -166,8 +166,8 @@ github.com/cosmos/go-bip39 v1.0.0 h1:pcomnQdrdH22njcAatO0yWojsUnCO3y2tNoV1cb6hHY
 github.com/cosmos/go-bip39 v1.0.0/go.mod h1:RNJv0H/pOIVgxw6KS7QeX2a0Uo0aKUlfhZ4xuwvCdJw=
 github.com/cosmos/gogoproto v1.4.11 h1:LZcMHrx4FjUgrqQSWeaGC1v/TeuVFqSLa43CC6aWR2g=
 github.com/cosmos/gogoproto v1.4.11/go.mod h1:/g39Mh8m17X8Q/GDEs5zYTSNaNnInBSohtaxzQnYq1Y=
-github.com/cosmos/iavl v0.19.4 h1:t82sN+Y0WeqxDLJRSpNd8YFX5URIrT+p8n6oJbJ2Dok=
-github.com/cosmos/iavl v0.19.4/go.mod h1:X9PKD3J0iFxdmgNLa7b2LYWdsGd90ToV5cAONApkEPw=
+github.com/cosmos/iavl v0.19.7 h1:ij32FaEnwxfEurtK0QKDNhTWFnz6NUmrI5gky/WnoY0=
+github.com/cosmos/iavl v0.19.7/go.mod h1:X9PKD3J0iFxdmgNLa7b2LYWdsGd90ToV5cAONApkEPw=
 github.com/cosmos/keyring v1.1.7-0.20210622111912-ef00f8ac3d76 h1:DdzS1m6o/pCqeZ8VOAit/gyATedRgjvkVI+UCrLpyuU=
 github.com/cosmos/keyring v1.1.7-0.20210622111912-ef00f8ac3d76/go.mod h1:0mkLWIoZuQ7uBoospo5Q9zIpqq6rYCPJDSUdeCJvPM8=
 github.com/cosmos/ledger-cosmos-go v0.11.1 h1:9JIYsGnXP613pb2vPjFeMMjBI5lEDsEaF6oYorTy6J4=

store/iavl/store.go

@@ -281,7 +281,7 @@ func (st *Store) Export(version int64) (*iavl.Exporter, error) {
 	if !ok || tree == nil {
 		return nil, fmt.Errorf("iavl export failed: unable to fetch tree for version %v", version)
 	}
-	return tree.Export(), nil
+	return tree.Export()
 }
 
 // Import imports an IAVL tree at the given version, returning an iavl.Importer for importing.