LOS ANGELES — Many from Metallica and the Foo Fighters rocked on with electrifying performances as family members gave heartfelt speeches in memory of the late Chris Cornell. Cornell’s wife, Vicky, stepped onstage struggling to speak at first. But after gathering herself, she eventually thanked everyone for their support and spoke about her husband’s legacy at his tribute concert called “I Am the Highway: A Tribute to Chris Cornell” on Wednesday night at the Forum in Inglewood, Calif. Cornell died at age 52 in May 2017.