Tuli Tuipulotu headlined a stingy defensive effort from No. 6 Southern Cal, which improved to 6–0 for the first time since 2006 with a 30–14 win over visiting Washington State on Saturday in Los Angeles. Tuipulotu finished with three sacks and four tackles for loss. The Trojans (6–0, 4–0 Pac-12) jumped out to a 10–0…