e415cc538a
The presentation timing logic (via `master_clock_get_swap_wait_time`) now works unconditionally. By "works" we mean that a result of zero from `master_clock_get_swap_wait_time` actually means zero now. Previously zero could mean either a successful result of zero milliseconds or that the backend couldn't get an answer. And a non-zero result is the same as before. This works even if the screen is "idle" and even if the backend doesn't provide presentation timestamps. So now our two fallback throttling mechanisms of relying on `CLUTTER_FEATURE_SWAP_THROTTLE` and decimating to `clutter_get_default_frame_rate` can be deleted. Closes: https://gitlab.gnome.org/GNOME/mutter/issues/406 and https://bugzilla.gnome.org/show_bug.cgi?id=781835 https://gitlab.gnome.org/GNOME/mutter/merge_requests/363