Fix a bug whereby a local (WC) diff showed all the properties of a locally
copied dir as "added" inatead of showing a diff against the copied-from dir.

* subversion/libsvn_wc/diff_editor.c
  (svn_wc__diff_local_only_dir): Correctly pass through the copy-from info
    for a locally copied dir.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1619380 13f79535-47bb-0310-9956-ffa450edef68