BRUSSELS — The laundry list for EU leaders when they head to Brussels for talks on Thursday and Friday is long and daunting: Ukraine, the Middle East, the bloc's massive multi-year budget, how to take on the economic might of China, plus the challenges posed by migration, defense and narcotics. It's no wonder that António Costa, the president of the European Council, has broken his rule that summits should last only one day (that and the fact that some of the leaders are coming straight from