* subversion/libsvn_repos/repos.h
  (svn_repos__parse_hooks_env): Note that if the input path is NULL,
    the out parameter will also be set to NULL.

Suggested by: danielsh

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1464132 13f79535-47bb-0310-9956-ffa450edef68