[mutter] window/wayland: Use constrained size when unmaximizing while fullscreen

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 425611eadf995e89dc2495c4662489762c55dc27
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Jun 13 10:34:23 2019 +0200

    window/wayland: Use constrained size when unmaximizing while fullscreen
    
    Otherwise we'll ask the client to use the size 0x0 with the fullscreen
    state set.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/621

 src/wayland/meta-window-wayland.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/src/wayland/meta-window-wayland.c b/src/wayland/meta-window-wayland.c
index 5ce67c689..db6476f19 100644
--- a/src/wayland/meta-window-wayland.c
+++ b/src/wayland/meta-window-wayland.c
@@ -217,9 +217,10 @@ meta_window_wayland_move_resize_internal (MetaWindow                *window,
    * coordinate space so that we can have a scale independent size to pass
    * to the Wayland surface. */
   geometry_scale = meta_window_wayland_get_geometry_scale (window);
-  if (flags & META_MOVE_RESIZE_UNMAXIMIZE)
+
+  if (flags & META_MOVE_RESIZE_UNMAXIMIZE &&
+      !meta_window_is_fullscreen (window))
     {
-      /* On un-maximize, let the client decide on its size */
       configured_width = 0;
       configured_height = 0;
     }