I'm renovating a bathroom, and there is one light fixture that I'd like to permanently remove. I know that I can't leave the junction box in the wall once the fixture is gone, but I have two related questions:
1) What is the best way to make it safe to drywall over the hole once the junction box is out?
2) How do I deal with the wires that are no longer needed for that fixture? Unfortunately, there is another light fixture that turns on with the same switch.
I'd really like to avoid having a cover since this is right at eye level.
Edit to include photos of what's currently in the wall. 
Best Answer
The cable in the wall have to be physically removed all the way to the other end, or if that is impracticable, as much as possible of both ends of the cables must be removed. It must be beyond any possibility of anyone ever energizing those wires again.
If there are multiple cables in the wall, then I mean both ends of each cable, including the far ends that are in other boxes.
If there are 2 cables and they need to remain in service, you can evaluate whether you have enough intact cable sheath to install a Tyco in-wall Romex splice. Those can be covered up.
Otherwise that through-cable run needs to be entirely replaced end-to-end.