Not quite. Federer doesn't care about Masters Series events nearly as much as GS's....so don't expect him to go all out to win. Not that he would win anyway.
I agree with the suggestion that Federer mainly plays for the GS's, which is something I've suspected for a while now. Of course, this doesn't mean he's tanking other tournaments, but not going all out, as you say.
However, I think tomorrow's game is actually worth going all out for, because there is so much to win out there.
I personally think Federer was hoping not to meet Nadal before RG, but now that he will, he must really go for it.
Also, if he wins tomorrow he's going to go to Roland Garros with a certain aura, being the only other player to win one of the main clay court events.
On the other hand if he loses, he won't even be the 2nd best at RG, because as it stands Djokovic is the man to beat after Nadal.
If Federer and Djokovic end up on the same side of the table in Paris, AND Federer loses tomorrow, then Djokovic takes him.