LONDON/TOKYO (Reuters) - Unrest in Hong Kong over Beijing's proposed national security laws weighed on global shares and oil prices on Wednesday, offsetting optimism about the re-opening of the world economy.Riot police fired pepper pellets on protesters in Hong Kong's main business district, rekindling concern about the protests seen last year that hit the territory's economy.MSCI's ex-Japan Asia-Pacific index fell 0.4%, as Hong Kong and mainland China shares extended declines.Hong Kong's Hang..