Trump delays tariffs on Chinese cellphones, laptops, toys; markets jump By David Shepardson and David Lawder   FILE PHOTO: U.S. President Donald Trump meets with China's President Xi Jinping at the start of their bilateral meeting at the G20 leaders summit in Osaka, Japan, June 29, 2019. REUTERS/Kevin Lamarque/File Photo   WASHINGTON (Reuters) - U.S. President Donald Trump on Tuesday backed off his Sept. 1 deadline for 10% tariffs on remaining Chinese imports, delay