Calling into upower works, and upower does pass the calls on to logind, but by the time they reach logind, they come from a root process (upowerd), and thus inhibitors don't quite have the same effect: You may get a polkit dialog if you hit the moon key, but not if you use the suspend menuitem. The easiest way to fix this is to call into logind directly.

At the same time, we should make the shell take a delay inhibitor while the shield is animating. Currently, gsd has to blindly wait for half a second to prevent the animation being cut in half by the suspend.