Stars Daniel Radcliffe, Emma Watson, Rupert Grint, and Tom Felton dropping their British accents to talk like they're from the United States. The four attempt to say very American phrases that we all, um, frequently toss around here, such as "Can I get an order of mozzarella sticks, please?" and "Justin Bieber is the man." At one point, they're even asked to -- gasp! -- dis "Twilight." Daniel apo…