“You Don’t Own Me: How Mattel v. MGA Entertainment Exposed Barbie’s Dark Side” by Orly Lobel, 2017, W.W.Norton, $27.95, 304 pages. As a kid, what was your favorite toy? You can probably remember it instantly: the thing you couldn’t bear to leave at home, the doll you spent hours with, the toy truck that road-tripped your imagination. Just thinking of it gives you a warm feeling and a wistful smile, but in “You Don’t Own Me” by Orly Lobel, you’ll read about two toy companies that weren’t playing around. Years after it happened, Carter Bryant couldn’t tell you what spurred him to think the way he did that sunny afternoon.