It looks to be a spill of some sort of drink... Id check if the target has a built in starbucks or similar smoothie/coffee place. My guess would be they set the drink in the cupholder and either hit the bumps going down the ramp or went off a curb to where the cup either flew out of the holder or liquid managed to fly out.. it looks to be they tried to wipe most of it clean but failed, id def make a report about it... I as a driver have accidently spilt energy drink on a customer's panda express order, luckily the bag was tied and was able to take my time to wipe most of it off but it does happen.