When filmmaker Lulu Wang set out to make a personal movie--largely set in China, mostly in Mandarin--she had a clear pitch, but buyers weren’t biting. She tells us about the circuitous route to making ‘The Farewell,’ which went from public radio piece to Sundance success to indie hit of the summer. Wang also explains the vagaries of filming in China and why she felt so strongly that her film had to play in theaters rather than finding a home on a streaming service.