Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

SoftBank's human-like robot named “Pepper” poses for pictures in its role as a PR manager of Tottori prefecture at the prefecture speciality store in Tokyo, Japan, July 1, 2015. Pepper will work at the store until July 2, as the first workplace venue for its temporary staffing service. (Photo by Yuya Shino/Reuters)

A boy uses remnants of ordnance as he prepares dough inside Abu Khaled's shop in the Douma neighborhood of Damascus April 28, 2015. Abu Khaled opened a shop for making “barley bread” using remnants of weapons including rockets, tank shells and other ordnance fired by forces loyal to Syria's President Bashar al-Assad. (Photo by Amer Almohibany/Reuters)

A man sits on the window of a burning building before falling from it, in central Lahore May 9, 2013. Fire erupted on the seventh floor of the LDA plaza in Lahore and quickly spread to higher floors leaving many people trapped inside the building. At least three people fell from the high floors trying to avoid fire that engulfed the building, local media reports. (Photo by Damir Sagolj/Reuters)

Women look at models standing in the David Hart presentation during Men's Fashion Week, in New York, July 13, 2015. The four-day event by the Council of Fashion Designers of America is the New York debut of Fashion Week: Men's. (Photo by Lucas Jackson/Reuters)

Yang Juan, an employee at Goopal Group, takes a nap in her seat after lunch, in Beijing, China, April 21, 2016. Office workers sleeping on the job is a common sight in China, where a surplus of cheap labour can lead to downtime at work. But in China's technology sector, where business is growing faster than many start-up firms can hire new staff, workers burn the midnight oil to meet deadlines and compete with their rivals. Some companies provide sleeping areas and beds for workers to rest during late nights. (Photo by Jason Lee/Reuters)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)