xwayland: Forward global position to X

xeyes works as expected now. subwindows are popped also as expected. This
patch should fix the following:

https://bugs.freedesktop.org/show_bug.cgi?id=59983

Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
diff --git a/src/compositor.c b/src/compositor.c
index 42011f5..d44ffaa 100644
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -728,6 +728,8 @@
 	weston_surface_damage_below(surface);
 
 	weston_surface_assign_output(surface);
+
+	wl_signal_emit(&surface->compositor->transform_signal, surface);
 }
 
 WL_EXPORT void
@@ -2778,6 +2780,7 @@
 	ec->wl_display = display;
 	wl_signal_init(&ec->destroy_signal);
 	wl_signal_init(&ec->activate_signal);
+	wl_signal_init(&ec->transform_signal);
 	wl_signal_init(&ec->kill_signal);
 	wl_signal_init(&ec->idle_signal);
 	wl_signal_init(&ec->wake_signal);