Was skipped on Windows and Mac before, now seen flaky also on Linux.

BUG=angleproject:1541

Change-Id: Ic993eeadb104989416607271ce100b02aea7cecc
Reviewed-on: https://chromium-review.googlesource.com/603087Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>