No, it says that the only way to heaven is through him. The "a belief in" part is something added by some Protestant evangelicals. (And no, "faith" is not identical to "a belief in," anymore than being faithful to your wife means believing she exists and that she married you.)
God saves. Man does not save. Man's belief in God does not save. God saves. He can save a little child who dies in a non-Christian environment never having known about Jesus, if he so desires. It's not for us to set limits on his grace and mercy.
It's really none of our business what God does or did with people who unavoidably die without hearing the Gospel. It is our business to preach the Gospel to those we can reach, and to concern ourselves with their salvation, and in particular, with the salvation of the person we see in the mirror.
That would seem a cruel pursuit, if through ignorance they were guaranteed entry into heaven, and thus by your "evangelism" you introduce to them "choice" and therefore the threat of hell.