Merge "Check sepolicy context for mounting vendor overlay"

    const auto vendor_mount_point = kVendorTopDir + mount_point;

    LINFO << "vendor overlay mount on " << vendor_mount_point;

    auto context = fs_mgr_get_context(vendor_mount_point);

    if (!context.empty()) {

        context = ",rootcontext="s + context;

    } else {

        PERROR << " result: cannot find the mount point";

    const auto target_context = fs_mgr_get_context(vendor_mount_point);

    if (target_context.empty()) {

        PERROR << " failed: cannot find the target vendor mount point";

        return false;

    }

    const auto source_directory = overlay_top + "/" + mount_point;

    const auto source_context = fs_mgr_get_context(source_directory);

    if (target_context != source_context) {

        LERROR << " failed: source and target contexts do not match (source:" << source_context

               << ", target:" << target_context << ")";

        return false;

    }

    auto options = "override_creds=off,"s + kLowerdirOption + overlay_top + "/" + mount_point +

                   ":" + vendor_mount_point + context;

    auto options =

            "override_creds=off,"s + kLowerdirOption + source_directory + ":" + vendor_mount_point;

    auto report = "__mount(source=overlay,target="s + vendor_mount_point + ",type=overlay," +

                  options + ")=";

    auto ret = mount("overlay", vendor_mount_point.c_str(), "overlay", MS_RDONLY | MS_RELATIME,