Building xwayland fails after refractor.

With the new commits which refactored Xwayland code building fails on Arch Linux.

[7/8] Compiling C object 'hw/xwayland/...nd@exe/xwayland-glamor-eglstream.c.o'.
FAILED: hw/xwayland/4b1b24b@@Xwayland@exe/xwayland-glamor-eglstream.c.o
[...]
../xserver/hw/xwayland/xwayland-glamor-eglstream.c: In function ‘xwl_eglstream_create_pending_stream’:
../xserver/hw/xwayland/xwayland-glamor-eglstream.c:500:37: error: implicit declaration of function ‘xwl_window_from_window’ [-Werror=implicit-function-declaration]
  500 |     struct xwl_window *xwl_window = xwl_window_from_window(window);
      |                                     ^~~~~~~~~~~~~~~~~~~~~~
../xserver/hw/xwayland/xwayland-glamor-eglstream.c:500:37: warning: nested extern declaration of ‘xwl_window_from_window’ [-Wnested-externs]
../xserver/hw/xwayland/xwayland-glamor-eglstream.c:500:37: warning: initialization of ‘struct xwl_window *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
../xserver/hw/xwayland/xwayland-glamor-eglstream.c:531:46: error: dereferencing pointer to incomplete type ‘struct xwl_window’
  531 |         xwl_eglstream->controller, xwl_window->surface, xwl_pixmap->buffer);
      |                                              ^~