[DO NOT MERGE] Update Security String to 2017-04-05 on lmp-dev am: e2eff3f7ee  -s ours am: ea757ba690 am: 37aab729cf  -s ours am: 8a59a2eda2 am: 3746e17d30 am: b15a2623ac am: 4be162ac7f  -s ours am: c8b7e08b50 am: 3e0d1c32da am: 437c3dd5d3
am: 21f6e17ffd

Change-Id: Ie5dc35c61122cfee38b11f5f4471c75ee0839b79