Baidu is investing about $10 million in IndoorAtlas to expand mapping services inside buildings and shopping centers as it steps up competition to e-commerce giant Alibaba Group Holding Ltd., according to a person familiar with the matter. The investment by China’s largest Web-search service values IndoorAtlas, which was founded in 2012 as a spinoff from the University of Oulu, Finland, at about $40 million to $50 million, said the person, who asked not to be identified because the investment isn’t public.