* The process will start by Firefox checking for an update in the background (as it does today).
* Once an update is found
** If the user needs to prompted for some reason, we show that promptat the normal time. (e.g, after 24 hours). If the user declines, we bail out.
** Otherwise, we go ahead and download the update (as a complete/partial MAR file) in the background.
* Once the download is finished, Firefox launches the updater binary in the background with the UI display disabled. Searching for new updates will be paused during this time.