[mutter] display: Fix tiling when grabbing an attached dialog

[Jasper St. Pierre <jstpierre src gnome org>]

commit 7cefe91c3cbe42297f76037db36ce1e2dcafffa0
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Mon Apr 28 17:17:53 2014 -0400

    display: Fix tiling when grabbing an attached dialog
    
    It seems we used the wrong variable by accident

 src/core/display.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/core/display.c b/src/core/display.c
index 192db10..21c444a 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -1810,8 +1810,8 @@ meta_display_begin_grab_op (MetaDisplay *display,
   display->grab_op = op;
   display->grab_window = grab_window;
   display->grab_button = button;
-  display->grab_tile_mode = window->tile_mode;
-  display->grab_tile_monitor_number = window->tile_monitor_number;
+  display->grab_tile_mode = grab_window->tile_mode;
+  display->grab_tile_monitor_number = grab_window->tile_monitor_number;
   display->grab_anchor_root_x = root_x;
   display->grab_anchor_root_y = root_y;
   display->grab_latest_motion_x = root_x;