This saves us ~15KiB per compiler instance on 32-bit Android.

BUG=492725

Change-Id: I9db2998482941b5ab2eb5cb4925cbd1fb58ab4be
Reviewed-on: https://chromium-review.googlesource.com/283584Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Tested-by: Jamie Madill <jmadill@chromium.org>