core/types: support for optional blob sidecar in BlobTx (#27841)

This PR removes the newly added txpool.Transaction wrapper type, and instead adds a way
of keeping the blob sidecar within types.Transaction. It's better this way because most
code in go-ethereum does not care about blob transactions, and probably never will. This
will start mattering especially on the client side of RPC, where all APIs are based on
types.Transaction. Users need to be able to use the same signing flows they already
have.

However, since blobs are only allowed in some places but not others, we will now need to
add checks to avoid creating invalid blocks. I'm still trying to figure out the best place
to do some of these. The way I have it currently is as follows:

- In block validation (import), txs are verified not to have a blob sidecar.
- In miner, we strip off the sidecar when committing the transaction into the block.
- In TxPool validation, txs must have a sidecar to be added into the blobpool.
  - Note there is a special case here: when transactions are re-added because of a chain
    reorg, we cannot use the transactions gathered from the old chain blocks as-is,
    because they will be missing their blobs. This was previously handled by storing the
    blobs into the 'blobpool limbo'. The code has now changed to store the full
    transaction in the limbo instead, but it might be confusing for code readers why we're
    not simply adding the types.Transaction we already have.

Code changes summary:

- txpool.Transaction removed and all uses replaced by types.Transaction again
- blobpool now stores types.Transaction instead of defining its own blobTx format for storage
- the blobpool limbo now stores types.Transaction instead of storing only the blobs
- checks to validate the presence/absence of the blob sidecar added in certain critical places

core/txpool/legacypool/legacypool.go

@@ -535,7 +535,7 @@ func (pool *LegacyPool) Pending(enforceTips bool) map[common.Address][]*txpool.L
 				lazies[i] = &txpool.LazyTransaction{
 					Pool:      pool,
 					Hash:      txs[i].Hash(),
-					Tx:        &txpool.Transaction{Tx: txs[i]},
+					Tx:        txs[i],
 					Time:      txs[i].Time(),
 					GasFeeCap: txs[i].GasFeeCap(),
 					GasTipCap: txs[i].GasTipCap(),
@@ -588,7 +588,7 @@ func (pool *LegacyPool) validateTxBasics(tx *types.Transaction, local bool) erro
 	if local {
 		opts.MinTip = new(big.Int)
 	}
-	if err := txpool.ValidateTransaction(tx, nil, nil, nil, pool.currentHead.Load(), pool.signer, opts); err != nil {
+	if err := txpool.ValidateTransaction(tx, pool.currentHead.Load(), pool.signer, opts); err != nil {
 		return err
 	}
 	return nil
@@ -900,26 +900,13 @@ func (pool *LegacyPool) promoteTx(addr common.Address, hash common.Hash, tx *typ
 	return true
 }
 
-// Add enqueues a batch of transactions into the pool if they are valid. Depending
-// on the local flag, full pricing contraints will or will not be applied.
-//
-// If sync is set, the method will block until all internal maintenance related
-// to the add is finished. Only use this during tests for determinism!
-func (pool *LegacyPool) Add(txs []*txpool.Transaction, local bool, sync bool) []error {
-	unwrapped := make([]*types.Transaction, len(txs))
-	for i, tx := range txs {
-		unwrapped[i] = tx.Tx
-	}
-	return pool.addTxs(unwrapped, local, sync)
-}
-
 // addLocals enqueues a batch of transactions into the pool if they are valid, marking the
 // senders as a local ones, ensuring they go around the local pricing constraints.
 //
 // This method is used to add transactions from the RPC API and performs synchronous pool
 // reorganization and event propagation.
 func (pool *LegacyPool) addLocals(txs []*types.Transaction) []error {
-	return pool.addTxs(txs, !pool.config.NoLocals, true)
+	return pool.Add(txs, !pool.config.NoLocals, true)
 }
 
 // addLocal enqueues a single local transaction into the pool if it is valid. This is
@@ -935,7 +922,7 @@ func (pool *LegacyPool) addLocal(tx *types.Transaction) error {
 // This method is used to add transactions from the p2p network and does not wait for pool
 // reorganization and internal event propagation.
 func (pool *LegacyPool) addRemotes(txs []*types.Transaction) []error {
-	return pool.addTxs(txs, false, false)
+	return pool.Add(txs, false, false)
 }
 
 // addRemote enqueues a single transaction into the pool if it is valid. This is a convenience
@@ -947,16 +934,20 @@ func (pool *LegacyPool) addRemote(tx *types.Transaction) error {
 
 // addRemotesSync is like addRemotes, but waits for pool reorganization. Tests use this method.
 func (pool *LegacyPool) addRemotesSync(txs []*types.Transaction) []error {
-	return pool.addTxs(txs, false, true)
+	return pool.Add(txs, false, true)
 }
 
 // This is like addRemotes with a single transaction, but waits for pool reorganization. Tests use this method.
 func (pool *LegacyPool) addRemoteSync(tx *types.Transaction) error {
-	return pool.addTxs([]*types.Transaction{tx}, false, true)[0]
+	return pool.Add([]*types.Transaction{tx}, false, true)[0]
 }
 
-// addTxs attempts to queue a batch of transactions if they are valid.
-func (pool *LegacyPool) addTxs(txs []*types.Transaction, local, sync bool) []error {
+// Add enqueues a batch of transactions into the pool if they are valid. Depending
+// on the local flag, full pricing contraints will or will not be applied.
+//
+// If sync is set, the method will block until all internal maintenance related
+// to the add is finished. Only use this during tests for determinism!
+func (pool *LegacyPool) Add(txs []*types.Transaction, local, sync bool) []error {
 	// Filter out known ones without obtaining the pool lock or recovering signatures
 	var (
 		errs = make([]error, len(txs))
@@ -1042,12 +1033,12 @@ func (pool *LegacyPool) Status(hash common.Hash) txpool.TxStatus {
 }
 
 // Get returns a transaction if it is contained in the pool and nil otherwise.
-func (pool *LegacyPool) Get(hash common.Hash) *txpool.Transaction {
+func (pool *LegacyPool) Get(hash common.Hash) *types.Transaction {
 	tx := pool.get(hash)
 	if tx == nil {
 		return nil
 	}
-	return &txpool.Transaction{Tx: tx}
+	return tx
 }
 
 // get returns a transaction if it is contained in the pool and nil otherwise.