The Upside Down has infiltrated McDonald's. To celebrate the release of the animated series Stranger Things: Tales from '85 , Netflix teamed up with McDonald's to create a themed Happy Meal. Here's what's in it, and when you can get it. What's in the Stranger Things Happy Meal? The Stranger Things: Tales from '85 Happy Meal includes several pieces of Stranger Things swag. Each meal comes with a custom Happy Meal box covered in artwork of the mutating Upside Down vines that wreak havoc in the series. Inside, fans will find a Stranger Things activity book and one of 12 collectible character toys. Promotional art for the collaboration reveals six of the toys: Stranger Things mainstays Lucas, Mike, Eleven, Dustin, Max, and Will. The other six options haven't been released yet, although they could range from Tales from '85 newcomer Nikki Baxter to figurines of the monsters the squad faces.…