init: Make /media a shared mount

ARC container is in its own mount namespace.
To allow ARC container to access disks mounted under /media,
/media should be a shared mount.

BUG=chromium:623548
TEST=grep media /proc/self/mountinfo

Change-Id: Ia24d2445121583766f19a2cd19b6229919c7a615
Reviewed-on: https://chromium-review.googlesource.com/356381
Commit-Ready: Ryo Hashimoto <hashimoto@chromium.org>
Tested-by: Ryo Hashimoto <hashimoto@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
1 file changed