Sync to the hardware refresh rate, not just 60.00Hz [performance]
The Clutter master clock supports three synchronization methods in order of preference:
(a) Hardware presentation times
(b) Swap throttling
(c) Fake vsync at 60.00Hz
X11 already supports all three but Wayland only has (c). This merge request implements both (a) and (b) for Wayland bringing it in line with X11.