Merged revision(s) 22206 from trunk/OpenMPT:

[Fix] On Windows XP, removing all groups from a list view disables grouping.
........


git-svn-id: https://source.openmpt.org/svn/openmpt/branches/OpenMPT-1.31@22207 56274372-70c3-4bfc-bfc3-4c3a0b034d27

mptrack/AdvancedConfigDlg.cpp

@@ -105,6 +105,7 @@ void COptionsAdvanced::ReInit()
 	if(m_listGrouped)
 	{
 		ListView_RemoveAllGroups(m_List.m_hWnd);
+		m_List.EnableGroupView();
 	}
 	m_List.SetItemCount(static_cast<int>(theApp.GetSettings().size()));