Magic. Joy. Happiness. Walt Disney’s creations have given us all of these feelings and more. Working Barn Productions presents the West Coast premiere of what The New York Times calls “a blackly comic inversion of the public Disney persona” — the ambitiously titled A Public Reading of an Unproduced Screenplay About the Death of Walt Disney by Lucas Hnath. In this fiercely funny, highly meta screenplay-within-a-play, the public persona of the self-made American folk hero, creator of “The Happiest Place on Earth,” is turned completely on its head.