It's unclear how this might happen, as it's during static map init,
but add a fail-safe to be sure.

BUG=526779

Change-Id: I5aa33f9bed30d4a8c1e9937a0b8c5fd11a7503d7
Reviewed-on: https://chromium-review.googlesource.com/302385Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Tryjob-Request: Jamie Madill <jmadill@chromium.org>
Tested-by: Jamie Madill <jmadill@chromium.org>