Stops the unintended 'User Rejected...' error caused by buggy submitt…

[danjm]

Fixes #1420

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1. Create a new wallet
2. Switch to the ropsten network
3. Go to the metamask faucet and get 1 eth for your Account 1
4. Create a new account, Account 2, so that your wallet has two accounts
5. Go to the metamask faucet and get 1 eth for your Account 2
6. Once the transaction is confirmed, go to your Transaction History
7. Now open the wallet sidebar and click "Send"
8. Send a transaction (this will be a transaction sent from account 2).
9. Wait for the transaction to confirm.
10. Switch to Account 1
11. go to your Transaction History
12. Now open the wallet sidebar and click "Send"
13. When you attempt to send this transaction, you will see the "User rejected this transaction" error, but when you cancel you will see that the transaction was submitted.

From this state, you can continuously recreate the error by doing the following:
14. Wait for the last transaction to confirm
15. Switch to Account 2
16. Repeat steps 7-13

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Explanation of why this is happening from the perspective of the code.

1. When the "Transaction History" is open, the TransactionView component mounts
2. On every update of the TransactionView component, its normalizeTransactions method is called
3. When in the send flow after having been on the transaction history page, the TransactionView component stays mounted. So when in this flow and confirming a transaction by clicking "Send", the normalizeTransactions method of TransactionView will be called.
4. normalizeTransactions compares the nonces of all submitted transactions to all confirmed transactions, if any of the submitted tx nonces are the same as the confirmedTx nonces, TransactionController.cancelTransaction is called on that submitted transaction.
5. Important: the confirmed transactions here includes all confirmed transactions from all accounts. If the just submitted transaction has a nonce equal to the nonce of an already confirmed transaction from another account then the cancelTransaction method mentioned in 4 will be called.
6. cancelTransaction causes an error to be emitted that causes the modal "User rejected..." message to be shown
7. However, step 5 and 6 happens after the TransactionController.approveTransaction method has been called and sent the transaction to the blockchain. Which is why the transaction still goes through

[andrepimenta]

Here couldn't we do:
tx => tx.transaction.nonce === transaction.transaction.nonce && tx.transaction.from === this.props.selectedAddress.toLowerCase()?

In this way we can remove the previous filter and we would do only 1 cycle. This would be noticeable in terms of performance if confirmedTxs possibly gets large.

What do you think?

[danjm]

I have addressed this in the latest commit

[andrepimenta]

I left a small comment about the filter, to see what you think.

But apart from that, all the logic and solution looks great! 👍

[ibrahimtaveras00]

Fix looks good, QA Passed 👍