I’m not sure why everybody is surprised that Google’s “new” (not new, been around for a while, just released to the public) url shortener can provide an extra piece of info known as a QR code. This is just Google’s url shortening crew being smart and using existing graphic/image APIs that Google provides to everybody. You want a QR code? Just plug in whatever text you want on the end of this url and you’ll get yourself a QR code.
Replace the final part chl= with whatever you want ie: chl=mypantsareonfire and you’ll get a QR code that resolves to just that. I’m sorry about your pants.