This is a preparation step to support idle_inhibit_unstable_v1 protocol.
As in Plasma powermanagement, screen locking, dpms, etc. is not
controlled by the wayland compositor but by external components through
the IdleTimeout interface the compositor needs a way to inhibit the idle
timeouts. So once idle_inhibit_unstable_v1 is implemented the compositor
can hook this up to the inhibit API in IdleInterface and thus inhibit
powermanagement, etc. as requested by the idle_inhibit_unstable_v1
The added API is straight forward:
- inhibit: inhibits idle timeouts
- uninhibit: uninhibits again
- inhibit and uninhibit must be called in pairs, so twice inhibit,
means uninhibit must be called twice
- isInhibited: whether it's inhibited
- and a signal that it changed
The signal is mostly used internally to stop the timers.