UPDATE 2-US trade-human rights link tests Obama-Russia ties

* U.S. "Magnitsky Act" clouds prospects for cooperation * Unlikely to affect Russia's stance on biggest issues * Moscow vows to respond in kind to bill to bar abusers * U.S. urges Russia to suspend meat import restrictions MOSCOW, Dec 8 (Reuters) - The U.S. Senate's passage oflegislation to punish Russians who violate human rights is thefirst big test of the resolve of Vladimir Putin and Barack ...