Cherry-pick MR for !607 by @bit-turtle.
Fixes a bug where the critical battery timer could still trigger thecritical battery action if the computer was charged while sleeping.
This adds a check to make sure the power level is still below thecritical level before running the action. (shutdown, sleep, etc.)
This bug could happen if the computer went to sleep while thecritical power notification was on screen.If the computer was charged and unplugged before returning from sleep,the critical battery timer would still trigger the action.
(cherry picked from commit 397182f4)