 Hong Kong is marking the 27th anniversary of its return from Britain to China. NPR's John Rewich reports the city's chief executive announced that Beijing is sending two pandas as gifts to mark the date. After a flag-raising ceremony in the morning, Chief Executive John Lee said the pandas will be arriving in a few months, and he offered his sincere thanks to the central government for its care and support of Hong Kong. The city has undergone sweeping political changes in recent years,