Add test for issue #4313 'replaced merges source causes assertion during
automatic merge'.

* subversion/tests/cmdline/merge_tests.py

  (auto_merge_handles_replacements_in_merge_source): New.

  (test_list): Add auto_merge_handles_replacements_in_merge_source.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1442808 13f79535-47bb-0310-9956-ffa450edef68