Though he lived in Silicon Valley, Linwei Ding spent months at a time in his native China, according to court papers.Nothing unusual about that — except that he was supposed to be working full time as a software engineer in Google’s San Francisco-area offices.Court records say he had others badge him into Google buildings, making it appear as if he were coming to work. In fact, prosecutors say, he was marketing himself to Chinese companies as an expert in artificial intelligence — while stealing...