Update Security String to 2017-12-05 for December Security
Bug: 67774760
(cherry picked from commit 81ee575d52e964d1a3933ac6e8e1a680321883a8)

Change-Id: If13823b2dc4c09eeb94544dbba45c65e1c58a307
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 01d1c98..5758d22 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 := 2017-12-01
+      PLATFORM_SECURITY_PATCH := 2017-12-05
 endif
 
 ifndef PLATFORM_BASE_OS