[mutter] wayland: Call assigned() surface role vfunc when re-assigned

[Jonas Ådahl <jadahl src gnome org>]

commit a5efa30f6c73ddb3c8a8601d908b6068a3bc6d19
Author: Jonas Ådahl <jadahl gmail com>
Date:   Fri Jul 1 15:30:21 2016 +0800

    wayland: Call assigned() surface role vfunc when re-assigned
    
    This will later be used by xdg-shell to ensure no buffer is attached on
    assignment.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=769936

 src/wayland/meta-wayland-surface.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/wayland/meta-wayland-surface.c b/src/wayland/meta-wayland-surface.c
index e671491..1c41e55 100644
--- a/src/wayland/meta-wayland-surface.c
+++ b/src/wayland/meta-wayland-surface.c
@@ -280,6 +280,8 @@ meta_wayland_surface_assign_role (MetaWaylandSurface *surface,
                            first_property_name, var_args);
       va_end (var_args);
 
+      meta_wayland_surface_role_assigned (surface->role);
+
       return TRUE;
     }
 }