The $70 billion company, the largest drug store chain in the U.S., is redefining the role of pharmacists and the pharmacy itself. Its new store design moves them out from behind the counter, freeing them from some administrative tasks and making them more available as frontline health-care consultants. In new private and semi-private rooms, they can review customer’s medications and administer blood pressure and blood-glucose tests. The overall emphasis of the stores, which feature a more open layout, is wellness. Walgreens is adding fresh food to its shelves and designating an iPad-equipped health guide to serve as a roaming health help desk for customers.