Updates from the 49ers' and Raiders' camps from Bee reporters Matthew Barrows and Paul Gutierrez: Raiders: Barnes gets banged up in the pile Khalif Barnes, locked in a battle at left tackle with Mario Henderson, injured his left ankle and knee when the scrum landed on him. "It's part of ball, and stuff like this happens, but it's frustrating," Barnes said as he was leaving the practice field to have an MRI. "The good part about it, I guess, is that it is earl...