Check document.URL for query-builder referrer too

It checks only for document.referrer which does work in context of
requests to wdqs (e.g. for Hadoop) but not for js (and being run inside
an iframe). We need to also check for document.URL too.

Bug: T269224
Change-Id: I7afd889202481648e4f70264d9a3747c45e0e484