miner: allow for extradata in post-merge blocks (ethereum#26387)

* miner: allow for extradata in post-merge blocks

* miner: nits

* miner: remove extradata checks

Author: MariusVanDerWijden

miner/worker.go

@@ -959,13 +959,12 @@ func (w *worker) commitTransactions(env *environment, txs *types.TransactionsByP
 
 // generateParams wraps various of settings for generating sealing task.
 type generateParams struct {
-	timestamp  uint64         // The timstamp for sealing task
+	timestamp  uint64         // The timestamp for sealing task
 	forceTime  bool           // Flag whether the given timestamp is immutable or not
 	parentHash common.Hash    // Parent block hash, empty means the latest chain head
 	coinbase   common.Address // The fee recipient address for including transaction
 	random     common.Hash    // The randomness generated by beacon chain, empty before the merge
 	noUncle    bool           // Flag whether the uncle block inclusion is allowed
-	noExtra    bool           // Flag whether the extra field assignment is allowed
 	noTxs      bool           // Flag whether an empty block without any transaction is expected
 }
 
@@ -1001,8 +1000,8 @@ func (w *worker) prepareWork(genParams *generateParams) (*environment, error) {
 		Time:       timestamp,
 		Coinbase:   genParams.coinbase,
 	}
-	// Set the extra field if it's allowed.
-	if !genParams.noExtra && len(w.extra) != 0 {
+	// Set the extra field.
+	if len(w.extra) != 0 {
 		header.Extra = w.extra
 	}
 	// Set the randomness field from the beacon chain if it's available.
@@ -1225,7 +1224,6 @@ func (w *worker) getSealingBlock(parent common.Hash, timestamp uint64, coinbase
 			coinbase:   coinbase,
 			random:     random,
 			noUncle:    true,
-			noExtra:    true,
 			noTxs:      noTxs,
 		},
 		result: make(chan *newPayloadResult, 1),

miner/worker_test.go

@@ -568,7 +568,7 @@ func testGetSealingWork(t *testing.T, chainConfig *params.ChainConfig, engine co
 		}
 		_, isClique := engine.(*clique.Clique)
 		if !isClique {
-			if len(block.Extra()) != 0 {
+			if len(block.Extra()) != 2 {
 				t.Error("Unexpected extra field")
 			}
 			if block.Coinbase() != coinbase {