monitor-manager/xrandr: Trap DPMS changes
Apparently DPMSForceLevel() can fail to force a valid level sometimes.
Closes: #2857 (closed) Closes: gnome-shell#6883 (closed)
Edited by Jonas Ådahl
Apparently DPMSForceLevel() can fail to force a valid level sometimes.
Closes: #2857 (closed) Closes: gnome-shell#6883 (closed)