Fix an unitialised memory read identified by valgrind.  This occurs during merge_tests.py 35.
Fix an unitialised memory read identified by valgrind.  This occurs
during merge_tests.py 35.

* subversion/libsvn_diff/diff_file.c
  (find_identical_prefix): Don't look beyond endp.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1201002 13f79535-47bb-0310-9956-ffa450edef68

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