On 32-bit Android this change saves ~30KiB per compiler instance.

BUG=492725

Change-Id: I8bea48d57ee7eac0a0ee417035085c0d335aea09
Reviewed-on: https://chromium-review.googlesource.com/281047Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Dmitry Skiba <dskiba@google.com>