[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

Change-Id: I5b374785d84f6affc879a4bbd0705f1c6d09e0fa