Both nsISHEntry.URI and nsISHEntry isSubFrame are readonly, but also have a
setter. This is silly, so this patch removes the setter and makes them
modifiable.

The patch also renames nsISHEntry.setAsHistoryLoad() as setLoadTypeAsHistory(),
which makes it clearer that it modifies the loadType attribute.

--HG--
extra : rebase_source : 7772e2c1d90d4fd9f462f20c777d6eacc65801c5