Packaged foods giant H.J. Heinz Co., which is merging with Kraft Foods Group Inc., reported a 12% drop in revenue in the first quarter hurt by foreign currency exchange rates and inventory buildup in the year-ago period. Heinz, owned by Brazilian private-equity firm 3G Capital Partners LP's, shipped safety stock to retailers ahead of the launch of its data-analytic push in North America in the second quarter of 2014.