chroot_version_hooks.d: Address unit_test breakage in CQ from caches.

We need to make sure all the packages that are rebuilt because of the
protobuf uprev actually are rebuilt rather than relying on cached copies
of generated files.

BUG=chromium:932757
TEST=unit_test stage passes in CQ.

Change-Id: I5b4f4a44e1fcfb0e2f0a669261e04b8b1a9d06b1
Reviewed-on: https://chromium-review.googlesource.com/c/1476151
Tested-by: Allen Webb <allenwebb@google.com>
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Trybot-Ready: Allen Webb <allenwebb@google.com>
1 file changed