[DO NOT MERGE] Update Security String to 2018-01-01 from 2017-12-05
Bug: 69257226
(cherry picked from commit c53a14f1745cd302cb4951ed803679770ba584c4)

Change-Id: Idede70580873e4480735aa8dc6666d7e9ca12333
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 5758d22..d8f27b7 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -181,7 +181,7 @@
     #  It must be of the form "YYYY-MM-DD" on production devices.
     #  It must match one of the Android Security Patch Level strings of the Public Security Bulletins.
     #  If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
-      PLATFORM_SECURITY_PATCH := 2017-12-05
+      PLATFORM_SECURITY_PATCH := 2018-01-01
 endif
 
 ifndef PLATFORM_BASE_OS