It is called A Neighbor's Duty
I found that I had the same issue as you for Valley of the Four Winds. I think it is a quest that is given to you as a follow up and it isn't obvious that you should be getting another quest. But this quest links the chain together. You will get a couple quests after that from the guy you turn that into and then and then after doing that, there will be one more quest called A Lesson in Bravery: http://www.wowhead.com/npc=56312. Then, finally, you will be able to take off with Chen and Li Li to deal with the brewery and Chen's Masterpiece.
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