Move codec.RegisterCrypto and codec.Cdc to new packages (#6330)

* Move codec.Cdc to legacy_global.Cdc

* Update CHANGELOG.md

* Updates

* nit

* Fix imports

* Updates

* Use cosmos multisig instead of tendermint multisig everywhere

* Fix tests

* Rename legacy_global -> legacy

* Add doc.go

* Linting, move all RegisterCrypto calls to crypto/codec

* Update crypto/codec/amino.go

Co-authored-by: Federico Kunze <31522760+fedekunze@users.noreply.github.com>

crypto/codec/amino.go

@@ -0,0 +1,52 @@
+package codec
+
+import (
+	"github.com/tendermint/tendermint/crypto"
+	"github.com/tendermint/tendermint/crypto/ed25519"
+	"github.com/tendermint/tendermint/crypto/secp256k1"
+	"github.com/tendermint/tendermint/crypto/sr25519"
+
+	"github.com/cosmos/cosmos-sdk/codec"
+	"github.com/cosmos/cosmos-sdk/crypto/types/multisig"
+)
+
+var amino *codec.Codec
+
+func init() {
+	amino = codec.New()
+	RegisterCrypto(amino)
+}
+
+// RegisterCrypto registers all crypto dependency types with the provided Amino
+// codec.
+func RegisterCrypto(cdc *codec.Codec) {
+	cdc.RegisterInterface((*crypto.PubKey)(nil), nil)
+	cdc.RegisterConcrete(ed25519.PubKeyEd25519{},
+		ed25519.PubKeyAminoName, nil)
+	cdc.RegisterConcrete(sr25519.PubKeySr25519{},
+		sr25519.PubKeyAminoName, nil)
+	cdc.RegisterConcrete(secp256k1.PubKeySecp256k1{},
+		secp256k1.PubKeyAminoName, nil)
+	cdc.RegisterConcrete(multisig.PubKeyMultisigThreshold{},
+		multisig.PubKeyAminoRoute, nil)
+
+	cdc.RegisterInterface((*crypto.PrivKey)(nil), nil)
+	cdc.RegisterConcrete(ed25519.PrivKeyEd25519{},
+		ed25519.PrivKeyAminoName, nil)
+	cdc.RegisterConcrete(sr25519.PrivKeySr25519{},
+		sr25519.PrivKeyAminoName, nil)
+	cdc.RegisterConcrete(secp256k1.PrivKeySecp256k1{},
+		secp256k1.PrivKeyAminoName, nil)
+}
+
+// PrivKeyFromBytes unmarshals private key bytes and returns a PrivKey
+func PrivKeyFromBytes(privKeyBytes []byte) (privKey crypto.PrivKey, err error) {
+	err = amino.UnmarshalBinaryBare(privKeyBytes, &privKey)
+	return
+}
+
+// PubKeyFromBytes unmarshals public key bytes and returns a PubKey
+func PubKeyFromBytes(pubKeyBytes []byte) (pubKey crypto.PubKey, err error) {
+	err = amino.UnmarshalBinaryBare(pubKeyBytes, &pubKey)
+	return
+}