Why does the white/silver iPhone 7 Plus not have an ALS sensor?

About a month and a half ago I bought a matte black iPhone 7 Plus, just last week I decided that I wanted the silver and white iPhone 7 Plus instead so I bought one as I try and sell the black one. With both of them in my possession I can clearly see that the black 7 plus has an ALS sensor directly to the right of the proximity sensor, but on the white 7 plus you can't see an ALS sensor at all, just the camera and the proximity sensor. So why don't iPhone 7 Plus with white screens have an ALS sensor?