The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d9f77afefccb6fc2d4705647839a4056a55df4ad

commit d9f77afefccb6fc2d4705647839a4056a55df4ad
Author: Wenzhao Zang <wzang@chromium.org>
Date: Tue Feb 27 03:08:08 2018

cros: Add high resolution suffix for surprise me wallpapers

Bug:  815310 
Test: Turn on "Enable new wallpaper picker" in chrome://flags
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Id1907d83d5961c57413d4a5e2050e00680889f5b
Reviewed-on: https://chromium-review.googlesource.com/935754
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539386}
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/browser/chromeos/extensions/wallpaper_private_api.cc
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/browser/resources/chromeos/wallpaper_manager/js/constants.js
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/browser/resources/chromeos/wallpaper_manager/js/util.js
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/browser/resources/chromeos/wallpaper_manager/js/wallpaper_manager.js
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/test/data/chromeos/wallpaper_manager/unit_tests/api_mock.js
[modify] https://crrev.com/d9f77afefccb6fc2d4705647839a4056a55df4ad/chrome/test/data/chromeos/wallpaper_manager/unit_tests/event_page_unittest.js