* subversion/libsvn_fs/tree.c   (id_check_ancestor, id_is_parent): Check for errors when getting nodes.
* subversion/libsvn_fs/tree.c
  (id_check_ancestor, id_is_parent): Check for errors when getting nodes.

Patch by: Philip Martin <philip@codematters.co.uk>

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion