That was a pretty good lick to smash a windshield like that. Tough dude. Best wishes for a quick healing.
With that said, California does indeed allow lane splitting. Works for sport bikes; not so much touring types. Not for me either way. As for riding a dirt bike in the parking lot, many "dirt bikes" are equipped to be street legal. I started riding on the street and dirt in 1973. Back then, about the only street riders were club members, and it was very dangerous since the driving public held us in low regard. Now, over 15% of households has a MC, so even when they aren't riding, they are vividly aware of MC's. I do local and long distance riding and have covered 43 states so far, with the rest in view, and find it safer now than it has ever been. Always vulnerable, but I can't remember the last time I had to take evasive action due to others.
Again, Robert, heal well and soon.