This sounds like something ghost written by a police officer who just passed through a hearing for use of deadly force.
Basically they want to be able to distinguish between guns and non guns based on color rather than common sense. Is the guy holding up a bank? Probably real. Is the kid pointing at you and going "bang bang youre dead?" Probably not, even if he is black. Instead cops will get to say "oh he pointed a black gun shaped object at me, therefore I had to kill him immediately without pausing to consider the situation."
But the problem is that the penalty for this will be so infintesimally small that anyone wishing to do this for nefarious purposes will simply ignore the law, which is a stupid one anyway. I also note that they ommitted olive drab, which pisses me off to no end.
Also, it only mentions coatings. Since plastic isnt a coating and has the color within, you can still get a pink AR15 or a plum AK47 stock. Stupid legislators.