With Meson >=0.48.0 it is no longer necessary to pass the flag
"-D b_lundef=false" on FreeBSD.

The Meson option "b_lundef" need to be set to false on FreeBSD, because
the symbol "environ" is in crt1.o, which is not linked with shared
libraries. With Meson >=0.48.0 it is possible to set this option only
for FreeBSD. This patch changes meson.build to do that.

Fix unknown cursor in layer-shell example

xwayland: Introduce set_decorations event

Fix partial dependency in protocol/meson.build

Apply multiseat fixes to FreeBSD direct backend

This commit applies the multiseat fixes that are part of PR #1063 (
commits 964e0a50 and 47895d2) to the FreeBSD direct backend.

External dependencies in Meson do not have include_directories,
therefore "includes: true" means nothing for the wayland-client partial
dependency. Because of this, the -I CFLAGs for wayland-client are not
used by the build command. This commit fixes this by using compile_args.

Introduce wlr_multi_for_each_backend

buffer: disconnect clients that commit an unknown buffer type

Disable hardware cursors when capturing output

If this happens, something went really wrong and we should do more
than just logging an error. See [1].

[1]: wayland/weston#148

Assert all the things!

Also make the frame resource inert when sending "ready".

And use it in screencopy.

Send unique keymap file descriptors

To prevent wl_keyboard keymap being written to by clients, use a unique
file descriptor for each wl_keyboard resource.

Reference: weston, commit 76829fc4eaea329d2a525c3978271e13bd76c078

Add support for WLR_SESSION env variable

Valid values are "logind"/"systemd" and "direct". If WLR_SESSION is set,
only its value is potentially tried; it will not try any other option.

output-layout: don't expose outputs without a mode

Steal CRTCs from disabled outputs

This commit allows outputs that need a CRTC to steal it from
user-disabled outputs. Note that in the case there are enough
CRTCs, disabled outputs don't loose it (so there's no modeset
and plane initialization needed after DPMS). CRTC allocation
still prefers to keep the old configuration, even if that means
allocating an extra CRTC to a disabled output.

CRTC reallocation now happen when enabling/disabling an output as
well as when trying to modeset. When enabling an output without a
CRTC, we realloc to try to steal a CRTC from a disabled output
(that doesn't really need the CRTC). When disabling an output, we
try to give our CRTC to an output that needs one. Modesetting is
similar to enabling.

A new DRM connector field has been added: `desired_enabled`.
Outputs without CRTCs get automatically disabled. This field keeps
track of the state desired by the user, allowing to automatically
re-enable outputs when a CRTC becomes free.

This required some changes to the allocation algorithm. Previously,
the algorithm tried to keep the previous configuration even if a
new configuration with a better score was possible (it only changed
configuration when the old one didn't work anymore). This is now
changed and the old configuration (still preferred) is only
retained without considering new possibilities when it's perfect
(all outputs have CRTCs).

User-disabled outputs now have `possible_crtcs` set to 0, meaning
they can only retain a previous CRTC (not acquire a new one). The
allocation algorithm has been updated to do not bump the score
when assigning a CRTC to a disabled output.

output: make wlr_output_enable return a bool

layer-shell: add _v1 suffix

xdg-output: add _v1 suffix

output: introduce WLR_NO_HARDWARE_CURSORS