chroot_version_hooks: Cleanup protobuf dependencies following upgrade.

CQ-DEPEND=CL:1526361
BUG=chromium:937442
TEST=PreCQ Passes

Change-Id: Id9c995a063ed52f590f6434301a4e9d5cc27cc4d
Reviewed-on: https://chromium-review.googlesource.com/1531185
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Allen Webb <allenwebb@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
1 file changed