Remove the output state handling from the diff callback wrapper in libsvn_wc.

Since the merge code is now handling its own state, we don't have to stay
compatible with this previously only privately available api.

* subversion/include/private/svn_wc_private.h
  (svn_wc__wrap_diff_callbacks): Remove state arguments.

* subversion/libsvn_client/client.h
  (svn_client__get_diff_editor): Remove function, which would now just
    wrap svn_wc__wrap_diff_callbacks.

* subversion/libsvn_client/diff.c
  (diff_repos_repos): Wrap processor locally. Update caller.

* subversion/libsvn_client/repos_diff.c
  (svn_client__get_diff_editor): Remove function.

* subversion/libsvn_wc/diff_editor.c
  (wc_diff_wrap_baton_t): Remove unused variables.
  (wrap_dir_opened,
   wrap_dir_added,
   wrap_dir_deleted,
   wrap_dir_closed,
   wrap_dir_changed,
   wrap_file_added,
   wrap_file_deleted,
   wrap_file_changed): Remove calls to state handler.

  (wrap_node_absent): Remove function.

  (svn_wc__wrap_diff_callbacks): Remove unneeded initialization.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1440688 13f79535-47bb-0310-9956-ffa450edef68