+updowndota@ who wrote these tests. Any chance you have some cycles to help look into this?

And just to clarify, these failures appear when applying this CL[1]. The CL does not break any guarantees made by Mojo bindings, but it can affect the timing of arbitrary events. The failures therefore strongly imply that incorrect ordering assumptions being made somewhere, and this has been the case for all other blocking bugs which have been fixed so far.

[1] https://chromium-review.googlesource.com/c/chromium/src/+/1145692

Triage nag: This Chrome OS bug has an owner but no component. Please add a component so that this can be tracked by the relevant team.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bd1c8107acfd97298263d886d78cd527e95ff7e9

commit bd1c8107acfd97298263d886d78cd527e95ff7e9
Author: Ken Rockot <rockot@chromium.org>
Date: Tue Oct 16 15:27:10 2018

[arc] Fix some test expectations

Fixes some ArcVoiceInteractionFrameworkServiceTest expectations. These
expectations are not guaranteed by the test setup or execution, and only
pass today coincidentally due to timing of Mojo interface message
dispatch. Fortunately there is no reason why the expectations need to be
met under the given conditions, so they are simply removed here.

See linked bug for additional details regarding why timing may change
soon.

Bug:  872069 
Change-Id: If6d15c1db8224555f0476910d10e17afe2f3cbe1
Reviewed-on: https://chromium-review.googlesource.com/c/1281742
Commit-Queue: Ken Rockot <rockot@chromium.org>
Reviewed-by: Yue Li <updowndota@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599991}
[modify] https://crrev.com/bd1c8107acfd97298263d886d78cd527e95ff7e9/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service_unittest.cc