Import patch r48766:
  Make sure that a selector passed by object is never destroyed.
  Fixes an issue when a automatic allocated selector is passed by reference
  reported on root-dev.


git-svn-id: https://root.cern.ch/svn/root/branches/v5-34-00-patches@48767 27541ba8-7e3a-0410-8455-c3a389f83636