Fix issue #4444, "diffing move inside a copy asserts".

* subversion/libsvn_wc/diff_editor.c
  (svn_wc__diff_local_only_file): Skip deleted files when comparing
   against the working tree, like done in svn_wc__diff_local_only_dir().

* subversion/tests/cmdline/diff_tests.py
  (diff_move_inside_copy): Remove XFail marker.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1538519 13f79535-47bb-0310-9956-ffa450edef68