Two minor cleanups in the diff editor code, which were made visible by the
next to commit patch.

* subversion/libsvn_wc/diff_editor.c
  (walk_local_nodes_diff): Remove unneeded boolean which was just the same as
    not the two other variables.
  (wrap_file_changed): Don't provide files if they aren't modified.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1446331 13f79535-47bb-0310-9956-ffa450edef68