You know why China won't collapse any time in the near future, because China is NOT like any other nation is East Asia: it's a continental power, with vast resources to pull from, not to mention a large population.
China's rising labor cost isn't going to disintegrate China's growth because no other nation can build like China can and when the labor cost does goes up - which it will - it will be the cheapest place to get quality goods in the world, because after years of development in the country - education and what not -, China would have produced the largest amount of skilled labor thus producing cheap good quality goods. Do you honestly believe if India or even Vietnam were start to become the worlds factories, they will immediately make high quality goods or even effectively build factories to make the goods in the first place?
You are also forgetting China's own industries and enterprises, when foreign corporations do want to start pulling out of China, China will have their own industries giving jobs to the western regions when the East coast and central China become relatively developed - By 2020 there would be around 6 provinces with a GDP comparable to Russia. In the future China won't need to rely on westerners consuming Chinese goods because by then, it would be the Chinese consuming Chinese goods.
Currently China's GDP per capita is going on the same path as South Korea; South Korea's GDP per capita was roughly about the same as China today in the 1980's so you can bet your bloody arse that China will eventually overtake Turkey in GDP per capita. China isn't going to remain stagnant; It's own industry and domestic brands is going to bring China to the level of developed nation just like South Korea, Japan and Taiwan. Having foreign corporation into China is just a stepping stone for China to establish their own corporations.
And regards to the whole growth is slowing, that is China's plan to have a sustainable growth and to also close the monstrous income gap that you have been rambling about.
Seriously if you want to have a more objective viewpoint, you should read some sources that argues against your current sources, before deducing China is going to stupidly destroy itself... The Chinese, like other East Asians, are very adaptable people; Taiwan use to rely on cheap labor for growth, but when we could no longer compete with other places with cheaper labor like in the Mainland and Vietnam we changed our main income to information technology and other jobs of the sort, and even today Taiwan is still able to experience high growth rate, right now Taiwan's GDP per capita is higher than many European nations and even Japan. How do you think China, along with India, were the richest nation on the planet for almost two thousand years?