Cleanup hostname change fix and clarify log message

CHANGELOG.md

@@ -11,6 +11,7 @@ All notable changes to this project will be documented in this file.
   permissions. Also switch to new setup command.
 - Include module static files in build, required for Debian package build.
 - dynamicdns: Allow reading status as non-root.
+- config: Set current domainname again after hostname change.
 
 ### Changed
 - repro: Use firewalld provided SIP services.

plinth/modules/config/config.py

@@ -234,7 +234,7 @@ def _apply_changes(request, old_status, new_status):
 def set_hostname(hostname):
     """Sets machine hostname to hostname"""
     old_hostname = get_hostname()
-    old_domainname = get_domainname()
+    domainname = get_domainname()
 
     # Hostname should be ASCII. If it's unicode but passed our
     # valid_hostname check, convert to ASCII.
@@ -251,13 +251,10 @@ def set_hostname(hostname):
                                      old_hostname=old_hostname,
                                      new_hostname=hostname)
 
-    # Domain name should be ASCII. If it's unicode, convert to ASCII.
-    domainname = old_domainname
-
-    LOGGER.info('Changing domain name to - %s', domainname)
+    LOGGER.info('Setting domain name after hostname change - %s', domainname)
     actions.superuser_run('domainname-change', [domainname])
 
-   
+
 def set_domainname(domainname):
     """Sets machine domain name to domainname"""
     old_domainname = get_domainname()