By Andrew Holleran Dwayne “The Rock” Johnson pulled off a pretty great surprise this weekend. The longtime wrestling, football and entertainment star surprised his mom with a new room in her house. It’s the “Smackdown Room.” “In her homes she always has her “Smackdown Room” where she keeps the coolest Rock/DJ memorabilia but over the years they’ve become insanely crowded – so for her new home, I had these cool built ins made and just added only a few memorabilia items – Posters, University of Miami game balls, movie awards, championship titles etc. Figured she can add whatever she wants from h…