A protestor throws an item on police forces during scuffles on the Champs-Elysees avenue, Saturday, Dec. 15, 2018 in Paris. Paris police say 85 people have been detained in Paris on the fifth straight weekend of protests by the "yellow vests" movement, where thousands of people converged in the French capital. (AP Photo/Kamil Zihnioglu)

People wearing their yellow vests demonstrate Saturday, Dec. 15, 2018 in Marseille, southern France. The "yellow vest" movement, which takes its name from the fluorescent safety vests French motorists must all have in their vehicles, emerged in mid-November as a protest against fuel tax increases. (AP Photo/Claude Paris)

The sun sets over buildings in Milan, Italy, Friday, Dec. 14, 2018. The climate change conference, COP24, is closing today in Katowice, Poland. (AP Photo/Luca Bruno)

British Prime Minister Theresa May walks by the Union flag and the EU flag as she departs a media conference at an EU summit in Brussels, Friday, Dec. 14, 2018. European Union leaders expressed deep doubts Friday that British Prime Minister Theresa May can live up to her side of their Brexit agreement and they vowed to step up preparations for a potentially-catastrophic no-deal scenario. (AP Photo/Francisco Seco)

Dreamstime

FILE - In this July 29, 2013, file photo, Les Moonves arrives at the CBS, CW and Showtime TCA party at The Beverly Hilton in Beverly Hills, Calif. CBS is pledging $20 million in grants to 18 organizations dedicated to eliminating sexual harassment in the workplace as the network tries to recover from the scandal that forced the ouster of Moonves. CBS said Friday, Dec. 14, 2018 that the money will go toward helping the organizations expand their work and “ties into the company’s ongoing commitment to strengthening its own workplace culture.” (Photo by Jordan Strauss/Invision/AP, File)

FILE - In this Nov. 16, 2018, file photo, commuters ride a new zero emission electric buses in Porterville, Calif. The California Air Resources Board voted Friday, Dec. 14, 2018, to require that all new buses be carbon-free by 2029. Environmental advocates project that the last dirty buses will phase out by 2040. (Chieko Hara/The Porterville Recorder via AP, FIle)

FILE - In this Sept. 9, 2010, file photo, a massive fire following a pipeline explosion roars through a mostly residential neighborhood in San Bruno, Calif. The California Public Utilities Commission said Friday, Dec. 14, 2018, that an investigation by its staff found Pacific Gas & Electric Co. lacked enough employees to fulfill requests to find and mark natural gas pipelines. A U.S. judge fined the utility $3 million after it was convicted of six felony charges for failing to properly maintain a natural gas pipeline that exploded south of San Francisco in 2010, killing eight people. (AP Photo/Jeff Chiu, File)

Secretary of State Mike Pompeo, second from left, and Defense Secretary Jim Mattis right, shake hands with their Canadian counterparts Canadian Minister of Foreign Affairs Chrystia Freeland, second from right, and Canadian Minister of Defense Harjit Sajjan, left, as they conclude their news conference following a meeting at the State Department in Washington, Friday, Dec. 14, 2018. (AP Photo/Manuel Balce Ceneta)