This can protect against refactoring bugs when adding fields to an
aggregate-initialized struct.

Change-Id: Id2e9824a1adb8bf5dbdc3775dc59ee9f18c43412
Reviewed-on: https://chromium-review.googlesource.com/960324
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51907}