* Emtpy parameter.
* No argument.

Usually we run tests with two nodes, so when there's a conflict it's
always between the "main" node and the processing node, so we always
have a distributing node during conflict.

But when running with, for example, 2 nodes (the main node + 2 nodes),
the conflict might occur between the two processing nodes and after
the resolution we still don't have a distributing node.

When looking up a document by reference, using getDocumentValueList from
the context of a web site / web section might not find the documents,
depending on the predicates defined on the web site / web section.

This gadget looks up a document by reference, by using
getDocumentValueList on the context of the web section.
getDocumentValueList also applies the criterions from the context, but
because web page references are already unique, adding more criterions
can just cause the document to be not found and the gadget to display
the "No document" error.