Here's the link to the copy-and-pasted article. It's just one person's opinion or judgment, but certainly is a probable scenario:
http://www.rense.com/general59/theSunburniransawesome.htm
I agree to the idea that China definitely will not involve itself directly in the possible US-Iran conflict. In the nuclear era, true great powers (the power to destroy human civilization) will not fight a war with their worthy rivals unless they mean, per God's will, to commit the world to an immediate destruction. But they will have to, per their historical destiny or, at the personal/collective level, their genetically programmed impulse, fight through surrogate states. And in my opinion, any surrogate wars have the potential to escalate into a full fledged world war.
Whether they like it or not, Iran, North Korea, etc. are such surrogates. And even a surrogate nation has its own will and agenda. They do not necessarily have to be pushed to surrogate wars, they can ignite wars (recall the Korean war) instead.
If the USA launches a war against Iran, as it did Iraq, and if I were the Chinese or the Russian leadership, I certainly would see this US action as one more step to contain China (in desperate need of oil and already almost burst with anger at the Taiwan situation) or Russia (from super power to rags thanks to the US), I certainly would do all I could to help sabotage the US war effort, further damage the US relations with the rest of the world, and damage its already falling economy. Would any one of you not if you were Chinese or Russian?
Therefore, I think that China and Russia and all other countries that have political and economical interest in Iran and the Middle East will protect their own interest by sabotaging the US interest, all the way to an escalation of the war of an unanticipated degree. But any other signficant countries will avoid fighting a direct war against the US. Countries like the US, Russia, China, etc. are like world-class chess players, they will quit many steps before checkmate when they see it coming clearly, as long as they can see it coming (in many a historical case, they didn't).
And to go off topic, I think the nuclear-bundling policy may be the only effective way to avoid a nuclear war. For that reason, the nuclear powers should sit down and find a way to destroy all nuclear weapons. For God's sake, the US should love this idea as it has the most powerful conventional arsenal in this world!