Shelties can range in size from 15lbs on up to 25 I think, so my first guess would be a bunch of sheltie in there with those markings..........but then, I'm never real good with these breed guessing things, LOL
I have a few guesses but only will say GORGEOUS!!! This dog would be sought after for commercials and movies. From the glass and cracked eyes, I wonder if the dog is a merle? Sometimes there are merles that on first glance look anything but..... and pomeranians and shelties both come in merle options. Poms especially have a ton of color options. Pom mix?