Before Wiz Khalifa was riding high on the charts and dating Amber Rose, the “Black and Yellow” rapper was selling mixtapes in his school hallway, getting his name tatted on his arm, laughing to episodes of “Chappelle’s Show” and “The Boondocks,” and being rescued by his mother when his used Pontiac Bonneville broke down. Flash back to 2004 with Wiz on MTV’s “When I Was 17.”