Build with these GN args:

dcheck_always_on = true
is_debug = false
is_component_build = true
target_os = "chromeos"
use_goma = true
enable_nacl = false

Build and run all ash_unittests locally:

ninja -C out/Default -j500 -l99 ash_unittests && testing/xvfb.py out/Default/ash_unittests

Failures:

[ RUN      ] WallpaperControllerTest.ShowCustomWallpaperWithCorrectResolution
[205356:205356:0320/092359.300832:1213523945617:ERROR:wallpaper_controller.cc(1791)] Failed to decode user wallpaper at chrome_os_custom_wallpapers/small/user1@test.com-hash/user1@test.com-file Falls back to default wallpaper. 
[205356:205356:0320/092359.357330:1213524002115:ERROR:display_manager.cc(1986)] Could not find display:2200000001
[205356:206496:0320/092359.518048:1213524162835:ERROR:gl_context_virtual.cc(39)] Trying to make virtual context current without decoder.
[205356:205356:0320/092359.525174:1213524169959:ERROR:display_manager.cc(1986)] Could not find display:2200000002
[205356:206764:0320/092359.553421:1213524198206:ERROR:wallpaper_controller.cc(536)] The path chrome_os_custom_wallpapers/original/user1@test.com-hash/user1@test.com-file doesn't exist. Falls back to default wallpaper.
../../ash/wallpaper/wallpaper_controller_unittest.cc:1466: Failure
Value of: CompareDecodeFilePaths( {large_wallpaper_path, wallpaper_dir_->GetPath().Append(default_large_wallpaper_name)})
  Actual: false
Expected: true
[205356:206496:0320/092359.630865:1213524275651:ERROR:sync_point_manager.cc(136)] Client did not release sync token as expected
[205356:206496:0320/092359.638489:1213524283275:ERROR:sync_point_manager.cc(136)] Client did not release sync token as expected
[205356:206496:0320/092359.651499:1213524296286:ERROR:gl_context_virtual.cc(39)] Trying to make virtual context current without decoder.
[205356:205356:0320/092359.657891:1213524302677:ERROR:wallpaper_controller.cc(1791)] Failed to decode user wallpaper at chrome_os_custom_wallpapers/original/user1@test.com-hash/user1@test.com-file Falls back to default wallpaper. 
[205356:205356:0320/092359.661433:1213524306218:ERROR:display_manager.cc(1986)] Could not find display:2200000003
[205356:206764:0320/092359.716857:1213524361643:ERROR:wallpaper_controller.cc(536)] The path chrome_os_custom_wallpapers/original/user1@test.com-hash/user1@test.com-file doesn't exist. Falls back to default wallpaper.
../../ash/wallpaper/wallpaper_controller_unittest.cc:1480: Failure
Value of: CompareDecodeFilePaths( {large_wallpaper_path, wallpaper_dir_->GetPath().Append(default_large_wallpaper_name)})
  Actual: false
Expected: true

Maybe something wrong with paths? Use scoped temp dir?

WallpaperControllerTest.PreventReloadingSameWallpaper is also flaky, maybe related?

 Issue 786266  "WallpaperControllerTest.MojoWallpaperObserverTest is flaky" sounds familiar.