CARSON, Calif. — I had been in Los Angeles for less than 12 hours, and the first indication I got that the Chargers even existed was when two dudes at a breakfast diner overheard me talking to a server about why I was in town, which was to write a story about the Chargers. “Aw, nobody cares about them,” one offered. Two days in Southern California would do little to disprove this assessment. The Chargers won 12 games this season, which tied for the best record in the AFC. They have a Hall of Fame quarterback in Philip Rivers, one of the league’s few remaining workhorse backs in Melvin Gordon, and a dynamic roster full of young defensive talents like ends Melvin Ingram and Joey Bosa, plus rookie safety Derwin James. They’re in the playoffs for just the second time in the last nine years, with a wild-card game across the country at the Baltimore Ravens set for Sunday. The rest of the nation has noticed the Chargers are pretty damn good. What about Los Angeles? Advertisement After 56 seasons in San Diego, the Chargers returned last year to L.A., the franchise’s very first home. Only they have no roots…