sandbox: upgraded to latest version

Upgraded sys-apps/sandbox to version 2.6-r1 on amd64, arm, x86

Includes some bug fixes like leaking fd's.

BUG=None
TEST=`cbuildbot chromiumos-sdk` works

Change-Id: Ic551a0f08bc8834c26fbd84dc11f09bccb712d49
Reviewed-on: https://gerrit.chromium.org/gerrit/33066
Reviewed-by: David James <davidjames@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
9 files changed