Northridge Fashion Center has made its extended holiday hours permanent. The shopping center hours have been extended on weekends, now opening at 8 a.m. and closing at 10 p.m. on Saturdays, and closing at 10 p.m. on Fridays. Shopping center owner General Growth Properties Inc. said that a poll of shoppers showed that 65 percent wanted the extended holiday hours throughout the year. “Consumers’ shopping habits have changed. Our new hours fall in line with the hours our customers requested,” said Lisa Avakian, senior marketing manager for the mall.