Revision 1619452

Fix the copy-from revision number reported in a diff header. It previously
reported 'nonexistent' instead of the copy-from revision in some cases.

1.8.x showed inconsistent revision indications in the diff '---' header in
different scenarios -- the copy-from revision in some cases, 'revision 0' in
some cases, possibly other indications in other cases. This fix doesn't make
everything great but just reduces the degree of inconsistency a little.

* subversion/libsvn_client/diff.c
  (diff_file_added, diff_dir_added): Pass on the copy-from revision number.

* subversion/tests/cmdline/diff_tests.py
  (diff_git_format_wc_wc,
   diff_local_copied_dir): Update the expected output.