[metacity] display: fix copy/paste error

[Alberts Muktupāvels <muktupavels src gnome org>]

commit d30ff9ebbde262b30d1d3054be3c9fae68507190
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Tue Apr 25 21:47:14 2017 +0300

    display: fix copy/paste error
    
    Commit 23fcfbf17ed493f8df5e2059422b5bbd51b23da2 was supposed to
    use alarm_window not display->grab_window...
    
    https://git.gnome.org/browse/mutter/commit/?id=7743c70d4753e1bd299f59e3f252257464031ff2

 src/core/display.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/core/display.c b/src/core/display.c
index 1a3acfc..c00cf0d 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -1787,7 +1787,7 @@ event_callback (XEvent   *event,
           value = ((XSyncAlarmNotifyEvent *) event)->counter_value;
           new_counter_value = XSyncValueLow32 (value) + ((gint64) XSyncValueHigh32 (value) << 32);
 
-          meta_window_update_sync_request_counter (display->grab_window, new_counter_value);
+          meta_window_update_sync_request_counter (alarm_window, new_counter_value);
 
           filter_out_event = TRUE; /* GTK doesn't want to see this really */
         }