From Allstate, CME Group and McDonald's to Motorola Mobility and Walgreens Boots Alliance, it's hard to think of a big company in metro Chicago that's not cutting head office staff. Corporate headquarters operations that created good jobs for generations of Chicagoans have turned into drivers of unemployment in recent years. Total headcount at Chicago's 10 biggest companies fell 5.6 percent last year. And data from Chicago outplacement firm Challenger Gray & Christmas show big, locally based companies contributing an outsized share of nearly 90,000 layoffs in Illinois since 2013. Kraft Heinz joined the parade on Aug. 12, cutting 700 of...