Inside the gleaming mall here on the Sunday before Christmas, just one thing was missing: shoppers. The upbeat music of “Jingle Bell Rock” bounced off the tiles, and the smell of teriyaki chicken drifted from the food court, but only a handful of stores were open at the sprawling enclosed shopping center. A few visitors walked down the long hallways and peered through locked metal gates into vacant spaces once home to retailers like H&M, Wet Seal and Kay Jewelers.