Royal canin have a Yorkshire Terrier brand alright.
Though I swapped to the Acana myself after reading how much better the Acana is. My sister was talking to a woman in the doggie daycare (one of the employees) and they said that royal canin used to be one of the better ones but they don't have as much meat in them since they got bought over.
I'm only going by what I've been told there but one thing I do know is that Lu's tear stains went away after swapping her food