fix: correct txcount used for deadlock detection

This commit fixes a bug in the way txCount was used for detecting and
aborting empty blocks. Previously, txCount was incremented immediately
after popping off the new transaction but before it is executed. This
was incorrect, as the transaction can still be rejected for nonce/gas
errors later on. Instead, we modify the logic only count transactions
that are successfully added, and utilize the existing w.current.tcount
member to implement the detection.

l2geth/miner/worker.go

@@ -783,11 +783,6 @@ func (w *worker) commitTransactions(txs *types.TransactionsByPriceAndNonce, coin
 	}
 
 	var coalescedLogs []*types.Log
-	// UsingOVM
-	// Keep track of the number of transactions being added to the block.
-	// Blocks should only have a single transaction. This value is used to
-	// compute a success return value
-	var txCount int
 
 	for {
 		// In the following three cases, we will interrupt the execution of the transaction.
@@ -808,7 +803,7 @@ func (w *worker) commitTransactions(txs *types.TransactionsByPriceAndNonce, coin
 					inc:   true,
 				}
 			}
-			return atomic.LoadInt32(interrupt) == commitInterruptNewHead
+			return w.current.tcount == 0 || atomic.LoadInt32(interrupt) == commitInterruptNewHead
 		}
 		// If we don't have enough gas for any further transactions then we're done
 		if w.current.gasPool.Gas() < params.TxGas {
@@ -821,8 +816,6 @@ func (w *worker) commitTransactions(txs *types.TransactionsByPriceAndNonce, coin
 			break
 		}
 
-		txCount++
-
 		// Error may be ignored here. The error has already been checked
 		// during transaction acceptance is the transaction pool.
 		//
@@ -890,7 +883,7 @@ func (w *worker) commitTransactions(txs *types.TransactionsByPriceAndNonce, coin
 	if interrupt != nil {
 		w.resubmitAdjustCh <- &intervalAdjust{inc: false}
 	}
-	return txCount == 0
+	return w.current.tcount == 0
 }
 
 // commitNewTx is an OVM addition that mines a block with a single tx in it.