Fix another O(n^2) commit performance issue: Replace O(n^2) dirent lookup code with O(n log n) lookup.
Fix another O(n^2) commit performance issue:
Replace O(n^2) dirent lookup code with O(n log n) lookup.

* subversion/libsvn_fs_fs/dag.c
  (svn_fs_fs__dag_delete): use direct access to dirent

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