Update Security String to 2019-08-05
Bug:126590667
(cherry picked from commit a3e1c57a95d895fff372054205914bc322b025a1)

Change-Id: I354c4bd2f2c5070d4a8eece477ed1bbc748cfdad
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index a8487e5..0e64739 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 := 2019-07-05
+      PLATFORM_SECURITY_PATCH := 2019-08-05
 endif
 
 ifndef PLATFORM_SECURITY_PATCH_TIMESTAMP