Replicate r1653608 from FSFS in FSX.  This prelimininarily fixes a segfault in the DAG traversal code.  That whole code section is slated for rework.
Replicate r1653608 from FSFS in FSX.  This prelimininarily fixes a segfault
in the DAG traversal code.  That whole code section is slated for rework.

* subversion/libsvn_fs_x/tree.c
  (open_path): Update HERE at the beginning instead at the end of each
               iteration to ensure its validity during the first iteration.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1657115 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion