Make sure the clones are register both with the underlying tree and the TChain...

Make sure the clones are register both with the underlying tree and the TChain itself (was missing until now).  This fixes <http://savannah.cern.ch/bugs/?88339>


git-svn-id: http://root.cern.ch/svn/root/trunk@41692 27541ba8-7e3a-0410-8455-c3a389f83636