Update Security String to 2017-05-01 on nyc-dev am: 573e7e75ca am: 368d0a8a42 am: 751d4cd04e am: e815842343 am: 4fae4a0fb1
am: 93887301f5

Change-Id: I5d339e57c396a90dfde446d7dc1a09c5c39b4e91