[DO NOT MERGE] Update Security String to 2019-05-01 in pi-dev
Bug: 128322951
(cherry picked from commit 1159bb8b17df6caf1ce075d120c811b17eb73554)

Change-Id: Ia20a2e166bb48eb879911f1e2086859a54e0826f
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 1df6fc5..7959341 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -231,7 +231,7 @@
     #  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 := 2019-04-05
+      PLATFORM_SECURITY_PATCH := 2019-05-01
 endif
 
 ifndef PLATFORM_SECURITY_PATCH_TIMESTAMP