Provide parsoid information to OCG if visual editor is installed.

The previous guard tested for the presence of [[Extension:Parsoid]],
which is not used outside of WMF installs, since its only job is to
manage the cache of parsoid output.  The variables referenced are
actually defined/used by [[Extension:VisualEditor]].

Change-Id: Ie1dbac73d851872a88e165bce0c2ee1ad83489c3