[mutter] core: Ensure we send SIGTERM only once to the zenity close dialog.

[Carlos Garnacho <carlosg src gnome org>]

commit 2d8d9dea97243cd846a30ced8599da774e9dce94
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Jul 14 16:39:24 2017 +0200

    core: Ensure we send SIGTERM only once to the zenity close dialog.

 src/core/meta-close-dialog-default.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/src/core/meta-close-dialog-default.c b/src/core/meta-close-dialog-default.c
index 55eb897..747a0ae 100644
--- a/src/core/meta-close-dialog-default.c
+++ b/src/core/meta-close-dialog-default.c
@@ -183,7 +183,10 @@ meta_close_dialog_default_hide (MetaCloseDialog *dialog)
     }
 
   if (dialog_default->dialog_pid > -1)
-    kill (dialog_default->dialog_pid, SIGTERM);
+    {
+      kill (dialog_default->dialog_pid, SIGTERM);
+      dialog_default->dialog_pid = -1;
+    }
 }
 
 static void