A Japanese YouTuber and two men were referred to prosecutors on Monday for allegedly placing a mattress on the sidewalk in front of the busy Shibuya scramble crossing in central Tokyo as part of a prank video, investigative sources said.Masahiro Harada, a 29-year-old YouTuber known as "Hezumaryu," and the two accomplices who appeared in the video are suspected of obstructing pedestrians on the sidewalk near the famous intersection on July 2 by laying out the Japanese-style futon mattress before one of them lay on it, according to the sources.Harada, who has traveled across Japan to create Y…READ FULL ARTICLE