Fixed invalid arrayify value in browser for SHA2-HMAC (#530).
Fixed invalid arrayify value in browser for SHA2-HMAC (#530).

ethers-io/ethers.js,ethers-io/ethers.js,ethers-io/ethers.js,ethers-io/ethers.js,ethers-io/ethers.js,ethers-io/ethers.js,ethers-io/ethers.js