If we don't have a valid canonical server and path to pass, there's no
point in returning a WikiReference that will fail in strange and unusal
ways.
This also documents that $wgServer/$wgCanonicalServer and $wgArticlePath
are required in SiteConfiguration.
Change-Id: Ib08011e9f1d0817a5d1bb165aba6b424785eaa6a
The mapping is not very good, but should be good enough, given
that only the URL parts are really being used.
Bug: T114107
Change-Id: I8186140aed5620cf7b4ba84aa4c9492c61f406d0
Given that the class is not constructed anywhere outside
of core the constructor can be altered without having to
worry about b/c.
Change-Id: Ie49c43a1724f05cb95a296dc0fad0f1c587d80ef
