DO NOT MERGE: Updating security string for pi-dev to 2018-06-05

Bug:78240102
Change-Id: I3956e7b1b2e7035fa36b3ca74eccd0d4fffeee95
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 698e221..c5a8b37 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -234,7 +234,7 @@
     #  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 := 2018-05-05
+      PLATFORM_SECURITY_PATCH := 2018-06-05
 endif
 
 ifndef PLATFORM_BASE_OS