They're a rudiment from the time when the extension had to be compatible
with both SFH_OBJECT_ARGS supporting and not versions of MediaWiki.
This is in the past, so unify them now by merging and or deleting the
old versions. The resulting functions don't end with "Obj" anymore.
One "common" function was left alone to be refactored at a later time,
however I've renamed it and made private.
Change-Id: Ice97e587bf7cc0469476c2e53268d2774ddfdd04