The power button on my Nextbit Robin has stopped working. After some investigation, it would appear that the volume down button doesn't work, either, so, I'm 99% certain that it's a software issue (related to taking a screenshot?); however, in the unlikely 1% chance, I don't want to just shut it down (through battery drain?), as it might not turn back on again if the issue is hardware related instead (whereas if I leave it as-is, it might as well last for a while as long as it never gets into a shutdown state).
It's possible to wakeup the phone by connecting or disconnecting it to a charger, and by installing a number of apps for the task, but it would appear that there is no way to actually reboot the phone, nor bring the Power-Off/Reboot menu that the power button normally brings.
How do I reboot the device?