As expected, the third and worst Mummy film starring Brendan Fraser has knocked “The Dark Knight” out of the No. 1 slot it occupied for 20 days. Steve Mason of Fantasy Moguls says that based on early Friday figures, “The Mummy: Tomb of the Emperor King” sold $16.5 million on Friday vs. $12.31 for TDK. He figures that translates into a tighter weekend finish than generally predicted, with “Mummy” still taking it over TDK by around $43.5M to $41M. Kevin Costner’s “Swing Vote” is DOA and will finish the weekend in sixth place with about $6M, behind “Step Brothers,” “Mamma Mia!” and Fraser’s other top 10 hit, the resilient “Journey to the Center of the Earth.”