Allow wrapped_fs to be set to None when closed by superclass.
Allow wrapped_fs to be set to None when closed by superclass.



git-svn-id: 74b2def6592cf29d88d1a5d33b5c4a2732d8507c@828 67cdc799-7952-0410-af00-57a81ceafa0f

alekibango/pyfilesystem,pscottdevos/pyfilesystem,duedil-ltd/pyfilesystem,pscottdevos/pyfilesystem,alekibango/pyfilesystem