Chrome ToT r479030 on Linux target_os=chromeos, release build

Run:
testing/xvfb.py out/Default/ash_unittests

These two tests initially fail every time:
[ RUN      ] AppListPresenterDelegateTest.SnapToFullscreenAfterSearchboxInput
../../ash/app_list/app_list_presenter_delegate_unittest.cc:211: Failure
Value of: app_list->is_fullscreen()
  Actual: false
Expected: true
[  FAILED  ] AppListPresenterDelegateTest.SnapToFullscreenAfterSearchboxInput (37 ms)
[5/1505] AppListPresenterDelegateTest.SnapToFullscreenAfterSearchboxInput (37 ms)
[ RUN      ] AppListPresenterDelegateTest.TapAndClickOutsideClosesPeekingAppList
../../ash/app_list/app_list_presenter_delegate_unittest.cc:234: Failure
Value of: app_list_presenter_impl()->GetTargetVisibility()
  Actual: false
Expected: true
../../ash/app_list/app_list_presenter_delegate_unittest.cc:239: Failure
Value of: app_list_presenter_impl()->GetTargetVisibility()
  Actual: false
Expected: true
[  FAILED  ] AppListPresenterDelegateTest.TapAndClickOutsideClosesPeekingAppList (37 ms)

They then pass on retry, but this slows down the test suite.

My GN args in case you have trouble reproducing:
dcheck_always_on = true
is_debug = false
is_component_build = true
target_os = "chromeos"
use_goma = true
enable_nacl = false

My guess is that something has to RunAllPendingInMessageLoop() or flush mojo.