Inclusion of groups in groups aren't taken into account when querying user memberships

This query is used to retreive groups memberships for a user. It won't match included groups.

from devs@xwiki.org :

I installed recently the 1.6 version of XWiki and found that a new
functionnality allows to add logical groups to the group members list :
great ! This recursive inclusion is properly managed in global rights (like
allowing a global group for accessing a space) but this does not seem to be
included in velo xwiki API. For example I have one client that belongs to
its company group XWiki.MyClientCompanyGroup that I added to the group
XWiki.Clients. I have a dedicated part of my menu for clients and I tests
whether the current user is a client or not with the test
`$xwiki.user.isUserInGroup("XWiki.Clients")` which always return false
Maybe a special macro could help... anyone has a clue ?

Query listGroupsForUser doesn't take group inclusion into account.
The query is used by XWikiGroupServiceImpl#listGroupsForUser(String, XWikiContext).

  <query name="listGroupsForUser">
    select doc.fullName from XWikiDocument as doc, BaseObject as obj, StringProperty as prop
    where obj.name = doc.fullName
      and obj.className='XWiki.XWikiGroups'
      and obj.id = prop.id.id and prop.id.name='member'
      and (prop.value=:username or prop.value=:shortname or prop.value=:veryshortname)
  </query>