I think that the Chinese involvement, if true, could be a sign of the ongoing closer military and security ties between China and Russia. The PLAN and the VMF have completed a recent large scale exercise in the Pacific and a smaller one earlier on in the Black Sea and Eastern Mediterranean. Russia does have military technology and skill sets that China needs and China the money that Russia needs. Russia has signed a significant gas deal with China and China does covet Russia's jet engine technology, especially the metallurgical side of things. They both want to keep the west out of central Asia and they both want to restrict what they determine as harmful foreign influences upon the region. They both have set up and are pushing their seperate integrated economic visions for the central Asian region. In Russia's case this is the Eurasian Economic Union (EEU) and in Chinas the Silk Road Economic Project which entails building infrastructures from China to its European markets.
Both of them are founding members of the Shanghai Cooperation Organisation and both had intended to combine the EEU and the Silk Road projects under the aegis of the SCO at the recent SCO summit. For some unstated reason that didn't happen. It is also thought that both Russia and China eventually want to move the SCO towards a security and military alliance along the lines of NATO. In such a partnership, especially one with China, Russia would have to accept that it is not the dominant partner economically or militarily. This brings us back to the original postulate that China is deploying troops to Syria.
This could be so. It would be a good and valuable learning experience for the PLA to be able to work alongside Russian forces in an operational war zone. This is IMHO them working together and I wouldn't be surprised to see more of it. Down the track, if a fully workable formal military alliance is formed and sustained between the two, it will create problems in Asia and wider Pacific area because China's back is protected allowing her to become even more assertive and in eastern Europe as Russia continues to nibble away at recovering former Soviet client states because China will have her back.
For the Middle East this could make any attempts to resolve any problems there more futile than what they are now because Russia and China will undoubtedly support each other in the UN and now Iran has two powerful "friends" who will support her against the west. That support will be conditional though - very much so.
