x11/window: Add proper type guard to x11-specific public API calls
These functions are specific for X11 windows only so we should check
if the passed window is an X11 one, not just a MetaWindow since we're
casting to the actual type at later point.
x11/window: Do not try to compare a wayland active window with X11
If a window sends a configure stacking request, we were comparing the
active window with the event window even though they were different
client types (e.g. wayland and x11).
This was leading to a critical error, so let's handle this by ensuring
that the active window is of the same kind of the event window before
doing x11-specific checks. Behaving as different applications in case.
backends/native: Add fake cursor plane using impl_device's crtcs
Because `meta_kms_impl_device_simple_initable_init` is called in the
middle of `meta_kms_device_new`, the crtcs list for `MetaKmsDevice`
has not been populated yet. And thus the loop to detect missing
cursor planes and create fake ones never iterated. But the crtcs list
does already exist in `MetaKmsImplDevice` so iterate over that instead.
wayland: Drop meta_wayland_keyboard_get_focus_client()
All its users did not necessarily depend on a MetaWaylandKeyboard
existing, so were ported to using the MetaWaylandSeat global input
focus. This may now be dropped.
