[DO NOT MERGE] Update Security String to 2018-01-01 Bug : 69257226 am:...

[DO NOT MERGE] Update Security String to 2018-01-01 Bug : 69257226 am: 7da2c1c4  -s ours am: 2a81f815  -s ours am: e9e54c59 am: 81099d1d am: 7d4d9a50 am: c4a00faf  -s ours am: 9381b6b1 am: c4233bcb am: 0f910b71 am: 78535d96 am: 6ee7f663  -s ours am: ec5ef1c8 am: e3a14845 am: f3020941
am: 201574c0  -s ours

Change-Id: Id7060656f5e79502aed78f7ccb97b872b8711e0b