feat(kcm): add revert timer
Description
Add a revert timer and an option for the user to revert the settings when they accidentally messed up the settings and unable to see the screen.
Screenshots
Migrated from https://phabricator.kde.org/D25539
Add a revert timer and an option for the user to revert the settings when they accidentally messed up the settings and unable to see the screen.
Migrated from https://phabricator.kde.org/D25539