Revert "Revert "Remove now-unusable 'setcon' command.""

This reverts commit b862bd00.

This change was fine but an earlier change it depended on was broken.
That change has been fixed and resubmitted.

Bug: http://b/19702273
Change-Id: I17e565721026e48e2a73526f729f2481d4d6edb5