Revert "[lacros] Exclude ui_base_unittests"

This reverts commit 3e86bdd3db60ed57028ce60f36df21e2c9b7d26a.

Reason for revert: Issue was fixed in https://chromium-review.googlesource.com/c/chromium/src/+/2321237.

Original change's description:
> [lacros] Exclude ui_base_unittests
> 
> Exclude ui_base_unittest from linux lacros builders due to a compile
> failure.
> 
> Bug: 1110072
> Change-Id: Ia228c2d6959d4821c2258d68bccb0a34d02bf02e
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2321244
> Reviewed-by: Sven Zheng <svenzheng@chromium.org>
> Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#792134}

TBR=liaoyuke@chromium.org,svenzheng@chromium.org

Change-Id: If91ef1a30c259cf819e0b4e8e5e85dec851ce7e6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1110072
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2324407
Reviewed-by: Yuke Liao <liaoyuke@chromium.org>
Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792433}