I don't doubt China's investment in Myanmar for a pipeline path and other things has been deeply regressive. I also don't really doubt that western action to restore some sense of democracy to Burma is going to include western goals regarding that pipeline and there probably isn't much China can do without a lot of pain. If they put too much energy into sustaining a junta in Myanmar their ability to grow support internationally from non coup-ridden nations will drop. And China wants those votes in the UN and associated bodies.