window: Reset tile monitor number when untiling

Otherwise we'll end up trying to access the out of date state later.

Fixes the following test failure backtrace:

    #0  _g_log_abort ()
    #1  g_logv ()
    #2  g_log ()
    #3  meta_monitor_manager_get_logical_monitor_from_number ()
    #4  meta_window_get_work_area_for_monitor ()
    #5  meta_window_get_tile_area ()
    #6  constrain_maximization ()
    #7  do_all_constraints ()
    #8  meta_window_constrain ()
    #9  meta_window_move_resize_internal ()
    #10 meta_window_tile ()

https://gitlab.gnome.org/GNOME/mutter/merge_requests/912

1 files changed, 4 insertions, 1 deletions

diff --git a/src/core/window.c b/src/core/window.c
index 5a0fdff63..b7894ecbb 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -3191,7 +3191,10 @@ meta_window_tile (MetaWindow   *window,
 
   /* Don't do anything if no tiling is requested */
   if (window->tile_mode == META_TILE_NONE)
-    return;
+    {
+      window->tile_monitor_number = -1;
+      return;
+    }
 
   if (window->tile_mode == META_TILE_MAXIMIZED)
     directions = META_MAXIMIZE_BOTH;