
Allow creating a queue of future times to tick at. This adds a new clock state where we let the clock go idle, but will wake at a time in the future to tick. We can still schedule ticks while in this new state, but we're assured a tick at or shortly after the scheduled time. This will be used later by wayland code that schedules future presentation. Signed-off-by: Derek Foreman <derek.foreman@collabora.com> Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3355>