Avoid F5 symbol clash.

Bug: chromium:770684
Change-Id: I9e851c1fe5abbdc4d032b7efdd0462c96d0c8ef3
Reviewed-on: https://chromium-review.googlesource.com/696063Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Mostyn Bramley-Moore <mostynb@vewd.com>
Cr-Commit-Position: refs/heads/master@{#48267}