[ENG-9905](https://linear.app/comm/issue/ENG-9905/update-secondary-device-login-to-match-whitepaper).
This is the first step of merging `BACKUP_DATA_KEY_MESSAGE` and `DEVICE_LIST_UPDATE_SUCCESS`. Initially, I wanted to make this code being part of `DEVICE_LIST_UPDATE_SUCCESS`, after `performLogIn` is done - that is how this will work in the future. However, we're now running on limited version of backup and there isn't anything to restore. Going to mention this in [ENG-992](https://linear.app/comm/issue/ENG-9921/revert-d13933-capturing-logs) in order to revert this.
Note:
It's not that easy to slice this into diffs, so it's possible that in the middle of the stack protocol is not working, it needs to be reviewed as a whole.
Depends on D13963