[DO NOT MERGE] Updating Security String to 2017-09-01 Bug:63846344 am: 4061effbfe am: e29d61d582 am: 775c752f51  -s ours am: 6399f470f6  -s ours am: 4a126acfa7
am: 4c9adca135  -s ours

Change-Id: I6c6632af2dc711301523e86637c4cbc6007a91ba