[evolution] Bug 764044 - Leftover "Generating message list" in the status pane

[Milan Crha <mcrha src gnome org>]

commit 7586e5e7e7a55dbfa0bd1e8cde537134851b490c
Author: Milan Crha <mcrha redhat com>
Date:   Wed Mar 28 10:22:59 2018 +0200

    Bug 764044 - Leftover "Generating message list" in the status pane

 src/mail/message-list.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)
---
diff --git a/src/mail/message-list.c b/src/mail/message-list.c
index c688e87..8fb54e9 100644
--- a/src/mail/message-list.c
+++ b/src/mail/message-list.c
@@ -3088,6 +3088,16 @@ message_list_dispose (GObject *object)
        if (message_list->priv->folder != NULL)
                mail_regen_cancel (message_list);
 
+       g_mutex_lock (&message_list->priv->regen_lock);
+
+       /* This can happen when the regen_idle_id is removed before it's invoked */
+       if (message_list->priv->regen_data) {
+               regen_data_unref (message_list->priv->regen_data);
+               message_list->priv->regen_data = NULL;
+       }
+
+       g_mutex_unlock (&message_list->priv->regen_lock);
+
        if (message_list->uid_nodemap) {
                g_hash_table_foreach (
                        message_list->uid_nodemap,