Hey, I'm the Debian maintainer of Grilo.
As upstream mentioned in bug #1119781, those tests don't need to be fixed because they never worked.
As far as I'm aware it was just an initial skeleton of a work that was never completed.
About splitting the Grilo plugins package, I also think it's a good idea, I would actually like to do that in Debian at some point.
Hey, I'm the Debian maintainer of Grilo.
As upstream mentioned in bug #1119781, those tests don't need to be fixed because they never worked.
As far as I'm aware it was just an initial skeleton of a work that was never completed.
About splitting the Grilo plugins package, I also think it's a good idea, I would actually like to do that in Debian at some point.