Let us all be reminded that Trent said one can be justified by baptism or the desire of it. Trent did not say they receive BAPTISM by the desire of it. You must distinguish between justification and baptism. Now, Trent did not fully explain this distinguishment (and I wish they had) but it is important. It begs the question of 'where does a justified person go, if they die before actually receiving the sacrament?' I don't know for certain, and the Church has not spoken on this matter. The point is, that Trent told us one can receive sanctifying grace (i.e. justification) by desire; She has never said that Baptism can be received in the same manner.