[evolution-data-server] [CamelOfflineFolder] Fix a runtime warning on application exit

[Milan Crha <mcrha src gnome org>]

commit 3c6be739560203a6dee79b8f13fcbeeaed07242a
Author: Milan Crha <mcrha redhat com>
Date:   Wed Jul 25 16:13:43 2018 +0200

    [CamelOfflineFolder] Fix a runtime warning on application exit
    
    Due to folder's parent store being already freed and a folder's "changed"
    signal being delivered within ESourceRegistry dispose, which flushes
    its main context, where the "changed" signal is scheduled and delayed.

 src/camel/camel-offline-folder.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)
---
diff --git a/src/camel/camel-offline-folder.c b/src/camel/camel-offline-folder.c
index b4935157b..dd6587c20 100644
--- a/src/camel/camel-offline-folder.c
+++ b/src/camel/camel-offline-folder.c
@@ -208,10 +208,12 @@ offline_folder_schedule_store_changes_job (gpointer user_data)
        g_mutex_lock (&offline_folder->priv->store_changes_lock);
        if (offline_folder->priv->store_changes_id == g_source_get_id (source)) {
                CamelSession *session;
+               CamelStore *parent_store;
 
                offline_folder->priv->store_changes_id = 0;
 
-               session = camel_service_ref_session (CAMEL_SERVICE (camel_folder_get_parent_store 
(CAMEL_FOLDER (offline_folder))));
+               parent_store = camel_folder_get_parent_store (CAMEL_FOLDER (offline_folder));
+               session = parent_store ? camel_service_ref_session (CAMEL_SERVICE (parent_store)) : NULL;
                if (session) {
                        gchar *description;
 
@@ -219,7 +221,7 @@ offline_folder_schedule_store_changes_job (gpointer user_data)
                           is replaced with a full path name. The spaces around “:” are intentional, as
                           the whole “%s : %s” is meant as an absolute identification of the folder. */
                        description = g_strdup_printf (_("Storing changes in folder “%s : %s”"),
-                               camel_service_get_display_name (CAMEL_SERVICE (camel_folder_get_parent_store 
(CAMEL_FOLDER (offline_folder)))),
+                               camel_service_get_display_name (CAMEL_SERVICE (parent_store)),
                                camel_folder_get_full_name (CAMEL_FOLDER (offline_folder)));
 
                        camel_session_submit_job (session, description,
@@ -259,7 +261,7 @@ offline_folder_maybe_schedule_folder_change_store (CamelOfflineFolder *offline_f
        }
 
        store = camel_folder_get_parent_store (CAMEL_FOLDER (offline_folder));
-       session = camel_service_ref_session (CAMEL_SERVICE (store));
+       session = store ? camel_service_ref_session (CAMEL_SERVICE (store)) : NULL;
 
        if (session && camel_session_get_online (session) && CAMEL_IS_OFFLINE_STORE (store) &&
            camel_offline_store_get_online (CAMEL_OFFLINE_STORE (store))) {
@@ -291,6 +293,9 @@ offline_folder_changed (CamelFolder *folder,
        CamelSession *session;
 
        store = camel_folder_get_parent_store (folder);
+       if (!store)
+               return;
+
        session = camel_service_ref_session (CAMEL_SERVICE (store));
 
        if (!session)
@@ -309,7 +314,7 @@ offline_folder_changed (CamelFolder *folder,
                   is replaced with a full path name. The spaces around “:” are intentional, as
                   the whole “%s : %s” is meant as an absolute identification of the folder. */
                description = g_strdup_printf (_("Checking download of new messages for offline in “%s : 
%s”"),
-                       camel_service_get_display_name (CAMEL_SERVICE (camel_folder_get_parent_store 
(folder))),
+                       camel_service_get_display_name (CAMEL_SERVICE (store)),
                        camel_folder_get_full_name (folder));
 
                camel_session_submit_job (
@@ -659,12 +664,17 @@ camel_offline_folder_can_downsync (CamelOfflineFolder *folder)
 {
        CamelService *service;
        CamelSettings *settings;
+       CamelStore *parent_store;
        CamelThreeState sync_folder;
        gboolean sync_store;
 
        g_return_val_if_fail (CAMEL_IS_OFFLINE_FOLDER (folder), FALSE);
 
-       service = CAMEL_SERVICE (camel_folder_get_parent_store (CAMEL_FOLDER (folder)));
+       parent_store = camel_folder_get_parent_store (CAMEL_FOLDER (folder));
+       if (!parent_store)
+               return FALSE;
+
+       service = CAMEL_SERVICE (parent_store);
        settings = camel_service_ref_settings (service);
 
        sync_store = camel_offline_settings_get_stay_synchronized (CAMEL_OFFLINE_SETTINGS (settings));