That is a new retail space to be incorporated into the MAX stop. It is replacing some unorganized storage for Saturday Market. I guess for the longest time, people were allowed to store there, but then some people stopped paying, left items behind when they moved out, and overall was poorly managed. Not sure what will go in here, but it will be a welcome change to the guy playing the diggery-do (spelling?).
YAY for the new Saturday Market.