Exposing libinput_tablet_tool from libinput allows compositors
to set tool specific configuration options like pressure range
and eraser button behavior.
See 'libinput_tablet_tool_*()' functions which require a
'libinput_tablet_tool' handle:
https://wayland.freedesktop.org/libinput/doc/1.30.0/api/group__config.html
(libinput 1.30.0, latest at the time of writing).
The documentation for wayland-server.h says:
> Use of this header file is discouraged. Prefer including
> wayland-server-core.h instead, which does not include the server protocol
> header and as such only defines the library PI, excluding the deprecated API
> below.
Replacing wayland-server.h with wayland-server-core.h allows us to drop the
WL_HIDE_DEPRECATED declaration.
This introduces -DWLR_USE_UNSTABLE and adds information regarding the
stability status to all headers. I started with a conservative set of
headers to mark as stable:
- types/wlr_matrix.h
- util/edges.h
- util/log.h
- util/region.h
- xcursor.h
