[libcros] add OWNERS TEST=None BUG=chromium-os:22007 Change-Id: I46f6d424898dc764658f6a4cd071eb3b056dea85 Signed-off-by: Elly Jones <[email protected]> Reviewed-on: https://gerrit.chromium.org/gerrit/19764 Reviewed-by: Satoru Takabayashi <[email protected]>