Following up on r1662794, make the checkout/switch/update logic in the python test framework use the standard run_and_verify_svn stderr handling, and replace the 4 singleton arguments of these functions with a completely optional extra_files args (which handles the only current usage in a better way than before), that verifies that these files are actually there.
In one case we still installed a singleton handler to allow extra files, but found no files since the introduction of tree conflicts. (Probably 1.6.0) The new code would return failure because the files are not here.
* subversion/tests/cmdline/svntest/actions.py (run_and_verify_checkout2, run_and_verify_checkout): Remove several arguments. Add dynamic keywords. Update caller. (verify_update): Define extra_files. Forward to disk comparison. (verify_disk): If extra_files is set, set singleton handlers and a (new) done handler. If needed we can add other tests this way. (run_and_verify_update, run_and_verify_merge): Remove some arguments. Add dynamic keywords. Use run_and_verify_svn. (run_and_verify_patch): Add dynamic keyword support. (run_and_verify_switch, run_and_verify_commit): Remove some arguments. Add dynamic keywords. Use run_and_verify_svn. (build_greek_tree_conflicts): Update caller.