Move lock guard to start of addOperation to protect isClosed() and isFinishing()
Move lock guard to start of addOperation to protect isClosed() and isFinishing()

CTRoundTable/Encrypted.Cash,CTRoundTable/Encrypted.Cash,bitcoinsSG/zcash,CTRoundTable/Encrypted.Cash,CTRoundTable/Encrypted.Cash,CTRoundTable/Encrypted.Cash,bitcoinsSG/zcash,bitcoinsSG/zcash,bitcoinsSG/zcash,bitcoinsSG/zcash,bitcoinsSG/zcash,CTRoundTable/Encrypted.Cash