Electronically scanned radars have just as much to do advancement of the electronic industry. Signal management is a combination of factors, including airframe design, hardware and software, and materials. You've got me on long range missiles though. That's completely aerospace.
The "Stealth" field itself is not solely dependent on how advanced a country's aerospace industry is though, but was constructed for its own purpose through a combination of other fields. With that in mind, I think it's hard to tell just how far along China is by pointing at any one industry. The US is far ahead by a good 50 years, but it's probably already developing technology that will be used in 6th and 7th generation platforms (the US's bottleneck is its political will, budget issues, and security needs). Meanwhile, China has the advantage of capitalizing on prior knowledge, a growing population of engineers, technological espionage, and a healthy dose of brain re-gain through scholars who began going abroad in the 70s. That said, I personally believe it's very hard to gauge where China's at particularly because it will continue to keep tight lipped until or even after first flight (at least until it finds benefit in doing otherwise), but I wouldn't advise gauging its progress solely by its aerospace industry (which while not top in the world, is quickly approaching "good enough" for the requirements of a 5th generation fighter).