[gimp] app: make sure crash-saving of open images to XCF doesn't call the GUI

[Michael Natterer <mitch src gnome org>]

commit eaddef595e9c4df688e0d64656c7df75eb316db7
Author: Michael Natterer <mitch gimp org>
Date:   Sun Jun 17 19:39:37 2018 +0200

    app: make sure crash-saving of open images to XCF doesn't call the GUI
    
    gimp_eek(): simply increase gimp->busy so XCF saving calling
    gimp_set_busy() and gimp_unset_busy() won't call the GUI layer and do
    whatever windowing system calls to set busy cursors.

 app/errors.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/app/errors.c b/app/errors.c
index 4996fd1dfe..1598470d61 100644
--- a/app/errors.c
+++ b/app/errors.c
@@ -454,6 +454,12 @@ gimp_eek (const gchar *reason,
    */
   if (backup_path)
     {
+      /* increase the busy counter, so XCF saving calling
+       * gimp_set_busy() and gimp_unset_busy() won't call the GUI
+       * layer and do whatever windowing system calls to set cursors.
+       */
+      the_errors_gimp->busy++;
+
       /* The index of 'XXX' in backup_path string. */
       num_idx = strlen (backup_path) - 7;