[mutter/gnome-3-32] window: Warn if try to focus unmanaging windows

[Florian Müllner <fmuellner src gnome org>]

commit 5efb11acadd9e344d15fd2e6ce1f6180a541975b
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Thu Feb 14 13:57:22 2019 +0100

    window: Warn if try to focus unmanaging windows
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/307
    (cherry picked from commit e14613e74e8c9bb8e08dc7a94e35a86c8baf7a01)

 src/core/window.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/core/window.c b/src/core/window.c
index d2c24506b..20caf1340 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -8562,6 +8562,8 @@ meta_window_shortcuts_inhibited (MetaWindow         *window,
 gboolean
 meta_window_is_focusable (MetaWindow *window)
 {
+  g_return_val_if_fail (!window->unmanaging, FALSE);
+
   return META_WINDOW_GET_CLASS (window)->is_focusable (window);
 }