LONDON — The News of the World, the British tabloid newspaper beset with a widening phone-hacking scandal, will shut down as result of the imbroglio, a top executive of its parent company said Thursday. The News, a feisty, hugely profitable daily that has been continuously published for 168 years, will cease publishing on Sunday, said James Murdoch, the son of media baron Rupert Murdoch, whose News Corp.