On the 1.7.x-issue4408 branch.

* subversion/libsvn_client/repos_diff_summarize.c
  (open_root): Pass full relpath so that svn_relpath_skip_ancestor
   doesn't return NULL, rename variable to avoid clash with type.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-issue4408@1514841 13f79535-47bb-0310-9956-ffa450edef68