BEIJING, April 21 (Reuters) - More than 40 years after Volkswagen stole the show at its first Chinese auto fair, it has lost its cutting-edge status in the country, with homegrown brands setting the pace for a younger generation of tech-hungry drivers. The combustion-engine heritage of "Made in Germany" no longer holds as much sway in what has become the world's largest car market, where local automakers are rolling out flashy, affordable electric vehicles that are essentially mobile phones on wheels. "Mayb ...