ClientUtil#extractBaseFromRdfModel returns null for a correct Base and null next Page

[berezovskyi]

org.eclipse.lyo.trs.client.util.ClientUtil#extractBaseFromRdfModel has a fall-though flow path:

if (ProviderUtil.isNotEmptySingletonArray(nextPageArray) && nextPageArray[0] instanceof Page) {
    nextPage = (Page) nextPageArray[0];
    baseObj.setNextPage(nextPage);
    log.debug("finished extracting base from rdf model");
    return baseObj;
}
log.debug("finished extracting base from rdf model");
// FIXME Andrew@2019-07-15: nulls
return null;

In which the default value returned is null despite having a valid (last) page of the base.