HOLLYWOOD — John Travolta made sure first time helmer Shainee Gabel knew what she was doing before signing on to star in “A Love Song for Bobby Long.”Gabel explained after the Variety screening of “Long” that Travolta interviewed her before agreeing to do the pic. “I forced her to give a very specific vision of what she had in mind,” Travolta explained. “I wanted to know ideas, shots, quality of the scene. I grilled her pretty her heavily,” he admitted. Co-star Gabriel Macht joked the he “grilled her pretty hard too,” before explaining how he actually nabbed his first major film role. Pete Hammond moderated the Dec. 14 ArcLight sesh.