BERLIN – In the fall of 2010, Liu Xia traveled to a prison in northeast China to tell her husband, dissident intellectual Liu Xiaobo, that he had just been awarded the Nobel Peace Prize. That was the last time she left home as a free woman. Until now. China allowed her to leave the country Tuesday, ending an eight-year house arrest that made the soft-spoken, chain-smoking 57-year-old poet with a shaven head a tragic icon known around the world. As Liu Xia came off a plane in Helsinki, Finland, to transfer to a flight to Berlin, she spread her arms and grinned widely at a waiting photographer.