It was introduced in the orginal commit 4d3148e0
"CWS-TOOLING: integrate CWS mba32issues01" but for copletely unclear reasons.
It looks like it serves as a placeholder for those "unknown-URI-scheme" cases
that shall go to RID_SVXPAGE_HYPERLINK_DOCUMENT, but for a news:// URI it would
make more sense to go to RID_SVXPAGE_HYPERLINK_MAIL anyway.  (Note that
INetURLObject only supports RFC 1738 news URIs that cannot have an authority
part, not RFC 5538 ones that allow for an optional authority part.)

Change-Id: I5db76fc2a733d0c334e24fecb9d7078bedbdbe08