[evolution] icalendar-importer: Can show incorrect time in imported data preview

[Milan Crha <mcrha src gnome org>]

commit c3b951431bc1bbb4a86bee1ce8ff3ef4b53a0352
Author: Milan Crha <mcrha redhat com>
Date:   Mon Nov 29 10:08:30 2021 +0100

    icalendar-importer: Can show incorrect time in imported data preview
    
    That happens when the .ics file does not contain timezones referenced
    by the component properties. Also check for the builtin timezones
    as if the TZID was a location.

 src/calendar/importers/icalendar-importer.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
---
diff --git a/src/calendar/importers/icalendar-importer.c b/src/calendar/importers/icalendar-importer.c
index f2ddcaa018..11f6a465f6 100644
--- a/src/calendar/importers/icalendar-importer.c
+++ b/src/calendar/importers/icalendar-importer.c
@@ -1207,7 +1207,6 @@ format_dt (const ECalComponentDateTime *dt,
 
        tt = e_cal_component_datetime_get_value (dt);
 
-       i_cal_time_set_timezone (tt, NULL);
        if (e_cal_component_datetime_get_tzid (dt)) {
                const gchar *tzid = e_cal_component_datetime_get_tzid (dt);
 
@@ -1216,8 +1215,13 @@ format_dt (const ECalComponentDateTime *dt,
                if (!i_cal_time_get_timezone (tt))
                        i_cal_time_set_timezone (tt, i_cal_timezone_get_builtin_timezone_from_tzid (tzid));
 
+               if (!i_cal_time_get_timezone (tt))
+                       i_cal_time_set_timezone (tt, i_cal_timezone_get_builtin_timezone (tzid));
+
                if (!i_cal_time_get_timezone (tt) && g_ascii_strcasecmp (tzid, "UTC") == 0)
                        i_cal_time_set_timezone (tt, i_cal_timezone_get_utc_timezone ());
+       } else if (!i_cal_time_is_utc (tt)) {
+               i_cal_time_set_timezone (tt, NULL);
        }
 
        if (i_cal_time_get_timezone (tt))