Add utils to estimate Scroll L1 gas

src/abis/external/L1GasPriceOracle.ts

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+export const L1_GAS_PRICE_ORACLE_ABI = [{"inputs":[{"internalType":"address","name":"_owner","type":"address"}],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"l1BaseFee","type":"uint256"}],"name":"L1BaseFeeUpdated","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"overhead","type":"uint256"}],"name":"OverheadUpdated","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"_oldOwner","type":"address"},{"indexed":true,"internalType":"address","name":"_newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"scalar","type":"uint256"}],"name":"ScalarUpdated","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"_oldWhitelist","type":"address"},{"indexed":false,"internalType":"address","name":"_newWhitelist","type":"address"}],"name":"UpdateWhitelist","type":"event"},{"inputs":[{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"getL1Fee","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"getL1GasUsed","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"l1BaseFee","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"overhead","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"scalar","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_l1BaseFee","type":"uint256"}],"name":"setL1BaseFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_overhead","type":"uint256"}],"name":"setOverhead","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_scalar","type":"uint256"}],"name":"setScalar","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_newWhitelist","type":"address"}],"name":"updateWhitelist","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"whitelist","outputs":[{"internalType":"contract IWhitelist","name":"","type":"address"}],"stateMutability":"view","type":"function"}] as const;

src/utils/gas.ts

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+import { BigNumber, Contract, Transaction, utils } from "ethers";
+import { CrocEnv } from "../croc";
+import { L1_GAS_PRICE_ORACLE_ABI } from "../abis/external/L1GasPriceOracle";
+
+/**
+ * Compute the raw transaction data for a given transaction.
+ * 
+ * ref: https://docs.ethers.org/v5/cookbook/transactions/#cookbook--compute-raw-transaction
+ */
+export function getRawTransaction(tx: Transaction) {
+  function addKey(accum: any, key: keyof Transaction) {
+    if (tx[key]) { accum[key] = tx[key]; }
+    return accum;
+  }
+
+  // Extract the relevant parts of the transaction and signature
+  const txFields = ["accessList","chainId","data","gasPrice","gasLimit","maxFeePerGas","maxPriorityFeePerGas","nonce","to","type","value"] as const;
+  const sigFields = ["v","r","s"] as const;
+
+  // Serialize the signed transaction
+  const raw = utils.serializeTransaction(txFields.reduce(addKey, { }), sigFields.reduce(addKey, { }));
+
+  // Double check things went well
+  if (utils.keccak256(raw) !== tx.hash) { throw new Error("serializing failed!"); }
+
+  return raw;
+}
+
+/**
+ * Estimates the additional L1 gas on Scroll for any data which is a RLP-encoded transaction with signature.
+ */
+export async function estimateScrollL1Gas(crocEnv: CrocEnv, rawTransaction: `0x${string}`): Promise<BigNumber> {
+  const crocContext = await crocEnv.context;
+  const chainId = crocContext.chain.chainId;
+  const isScroll = chainId === "0x82750" || chainId === "0x8274f";
+  if (!isScroll) {
+    return BigNumber.from(0);
+  }
+
+  const L1_GAS_PRICE_ORACLE_ADDRESS = "0x5300000000000000000000000000000000000002";
+  const l1GasPriceOracle = new Contract(L1_GAS_PRICE_ORACLE_ADDRESS, L1_GAS_PRICE_ORACLE_ABI, crocContext.provider);
+
+  // function getL1Fee(bytes memory _data) external view override returns (uint256);
+  const l1Gas = await l1GasPriceOracle.getL1Fee(rawTransaction) as BigNumber;
+  return l1Gas;
+}