Add 'mtp' user to baseline.

Now that https://gerrit.chromium.org/gerrit/#/c/29174/ landed.

BUG=chromium-os:33228
TEST=security_AccountsBaseline passes again.

Change-Id: I91452cffacdcb90c077cb229f3ec02d99aac862c
Reviewed-on: https://gerrit.chromium.org/gerrit/31258
Tested-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Jim Hebert <jimhebert@chromium.org>
Commit-Ready: Jorge Lucangeli Obes <jorgelo@chromium.org>
2 files changed