Lots of tests failing with a similar problem

==23070==ERROR: AddressSanitizer: heap-use-after-free on address 0x612000163858 at pc 0x000019634c31 bp 0x7ffd38884890 sp 0x7ffd38884888
READ of size 8 at 0x612000163858 thread T0 (chromevox_tests)
    #0 0x19634c30 in drivefs::DriveFsHost::MountState::OnMountEvent(chromeos::disks::DiskMountManager::MountEvent, chromeos::MountError, chromeos::disks::DiskMountManager::MountPointInfo const&) chromeos/components/drivefs/drivefs_host.cc:300:7
    #1 0x11216bd7 in chromeos::disks::(anonymous namespace)::DiskMountManagerImpl::NotifyMountStatusUpdate(chromeos::disks::DiskMountManager::MountEvent, chromeos::MountError, chromeos::disks::DiskMountManager::MountPointInfo const&) chromeos/disks/disk_mount_manager.cc:766:16
...

suspecting r600222

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a402339243b22acd8276913aff07564d66c2842d

commit a402339243b22acd8276913aff07564d66c2842d
Author: Christos Froussios <cfroussios@chromium.org>
Date: Wed Oct 17 08:36:27 2018

Revert "Enable the DriveFS experiment in fieldtrial_testing_config.json."

This reverts commit 5628afccb6a2d9901e9aff2c485a4a6c2de5316e.

Reason for revert: suspected of breaking tons of tests across many builders
E.g. https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Linux%20Chromium%20OS%20ASan%20LSan%20Tests%20%281%29/29615

Bug:  896163 

Original change's description:
> Enable the DriveFS experiment in fieldtrial_testing_config.json.
> 
> Bug: 819822, 891197
> Change-Id: Ie8daa2f97af0c0eadd4661ea4b28bbaa6a326839
> Reviewed-on: https://chromium-review.googlesource.com/c/1278431
> Commit-Queue: Sam McNally <sammc@chromium.org>
> Reviewed-by: Steven Holte <holte@chromium.org>
> Reviewed-by: Sergei Datsenko <dats@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#600222}

TBR=sammc@chromium.org,holte@chromium.org,dats@chromium.org

Change-Id: I8d45f9db89a7da5d48ecc2275ab08aefa4728a5b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 819822, 891197
Reviewed-on: https://chromium-review.googlesource.com/c/1286130
Reviewed-by: Christos Froussios <cfroussios@chromium.org>
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600316}
[modify] https://crrev.com/a402339243b22acd8276913aff07564d66c2842d/testing/variations/fieldtrial_testing_config.json

Fixed chromevox_tests, sync_integration_tests, interactive_ui_tests, mash_browser_tests, select_to_speak_extension_tests, possibly more that I missed

Assigning to the owner of the reverted CL.