Old PrepareProposal on feature/abci++ppp (#9106)

* [Rebased to v0.34.x] abci: PrepareProposal (#6544)

* fixed cherry-pick

* proto changes

* make proto-gen

* UT fixes

* generate Client directive

* mockery

* App fixes

* Disable 'modified tx' hack

* mockery

* Make format

* Fix lint

Co-authored-by: Marko <marbar3778@yahoo.com>

types/tx.go

@@ -92,6 +92,28 @@ func (txs Txs) Proof(i int) TxProof {
 	}
 }
 
+// ToSliceOfBytes converts a Txs to slice of byte slices.
+//
+// NOTE: This method should become obsolete once Txs is switched to [][]byte.
+// ref: #2603
+// TODO This function is to disappear when TxRecord is introduced
+func (txs Txs) ToSliceOfBytes() [][]byte {
+	txBzs := make([][]byte, len(txs))
+	for i := 0; i < len(txs); i++ {
+		txBzs[i] = txs[i]
+	}
+	return txBzs
+}
+
+// ToTxs converts a raw slice of byte slices into a Txs type.
+func ToTxs(txs [][]byte) Txs {
+	txBzs := make(Txs, len(txs))
+	for i := 0; i < len(txs); i++ {
+		txBzs[i] = txs[i]
+	}
+	return txBzs
+}
+
 // TxProof represents a Merkle proof of the presence of a transaction in the Merkle tree.
 type TxProof struct {
 	RootHash tmbytes.HexBytes `json:"root_hash"`