The function call will act as a precheck on Web resource access
error when accessing the open directly without the normal file
open procedure, e.g. accessing Web resource property values first.

An example of this direct open call are the extension fetching and
the extension update check.

Change-Id: I765a2fe29f432a07a649e5a35440ae351c681af9
Reviewed-on: https://gerrit.libreoffice.org/29454Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Giuseppe Castagno <giuseppe.castagno@acca-esse.eu>