[evolution] EWebDAVBrowser: Remove 'calendar-order' property when unset on save

[Milan Crha <mcrha src gnome org>]

commit eb2c40e236e7fa5d6734ee779346a6829a1ec629
Author: Milan Crha <mcrha redhat com>
Date:   Mon Mar 8 14:01:15 2021 +0100

    EWebDAVBrowser: Remove 'calendar-order' property when unset on save
    
    Otherwise the value cannot be unset on the server, keeping the previous
    value in use.

 src/e-util/e-webdav-browser.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/e-util/e-webdav-browser.c b/src/e-util/e-webdav-browser.c
index 2408daab78..f2ee3a0182 100644
--- a/src/e-util/e-webdav-browser.c
+++ b/src/e-util/e-webdav-browser.c
@@ -1716,6 +1716,8 @@ webdav_browser_save_changes_thread (EAlertSinkThreadJobData *job_data,
                                g_snprintf (order_str, sizeof (order_str), "%u", (guint) scd->order);
 
                                changes = g_slist_append (changes, e_webdav_property_change_new_set 
(E_WEBDAV_NS_ICAL, "calendar-order", order_str));
+                       } else {
+                               changes = g_slist_append (changes, e_webdav_property_change_new_remove 
(E_WEBDAV_NS_ICAL, "calendar-order"));
                        }
 
                        if (scd->description && *scd->description)