Me: 2FA: when re-enabling 2FA previous phone number is shown but buttons are not clickable

[v18]

Steps to reproduce:

1. Add 2FA to an account
2. Remove 2FA for that account
3. Try to add 2FA again. Here's what you see:

The buttons are disabled:

By typing another number in the phone field, the buttons are re-enabled:

This behaviour is correct when there isn't a phone number already saved in the phone field. When there is already a number saved there, the buttons should be available right away (one exception is in the case where it's been less than 1 minute since the last SMS for the SMS button).

The buttons should not be only reenabled when more text is typed or erased from the field.

[ebinnion]

After looking into this, I think the best way to approach this would be to refactor the component. Specifically, at least factoring out the getValue functionality so that we could build a phoneNumber object in the getInitialState lifecycle method of Security2faSettings.

I would prefer to tackle this in a maintenance period in December so that I can focus on people management, unless this is crucial to address right now. Also ping @mjangda who might have some bandwidth to address this sooner.

cc @beaulebens @designsimply

[v18]

This is related to #26 - both buttons can become disabled when cancelling the process and starting again

[ebinnion]

This should be fixed in #584.