This CL also includes the gcc build time dependency for building the
sock_ctrl_msg.c helper code.
TEST=cargo test
BUG=chromium:738638
Change-Id: I4adc2360b7fab4ed7d557603aa7bad2e738b69b4
Reviewed-on: https://chromium-review.googlesource.com/562574
Commit-Ready: Zach Reizner <zachr@chromium.org>
Tested-by: Zach Reizner <zachr@chromium.org>
Reviewed-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>