Hong Kong-born actor Jason Tobin says he had to get into the best shape of his life to play the role of Young Jun, a Chinese gang leader in 1870s San Francisco. Tobin stars in Warrior, a television show based on an original idea from martial arts legend and fellow Hongkonger Bruce Lee.  Warrior is developed from an eight-page treatment Bruce Lee wrote, that was later discovered by his daughter Shannon. The show runners had proposed that he would play the central character, martial arts prodigy…