A centerpiece of then-Gov. Dannel P. Malloy’s economic development policy was a 2014 deal with millions of dollars in tax credits earned by the company in exchange for a commitment by UTC to build a headquarters for UTC’s jet engine manufacturing subsidiary, Pratt & Whitney that will remain in Connecticut for at least 15 years. UTC also agreed to build a Pratt & Whitney engineering “center of excellence” in Connecticut and keep the corporate headquarters of Sikorsky, now owned by Lockheed Martin Corp., in Connecticut at least five years.