ISTANBUL Voters in Japan headed to polling stations Sunday to elect 125 lawmakers for the upper house of parliament, in a crucial test for the minority ruling coalition of Prime Minister Shigeru Ishiba. More than 104 million Japanese are eligible to cast ballots to elect the legislators in the House of Councilors, the upper house of National Diet, or parliament. Just 75 constituency seats are contested, while the remaining 50 will be elected through proportional representation. As of 10 am