Temporarily disable security checks.

There have been several obscure regressions that have been uncovered
as part of enabling these checks, and we'll need to design a more
holistic strategy for handling self-calls before enabling again.

Bug: 188391719
Test: none
Change-Id: I5720bed3f66ba87e52d0348157b29b921b869032
(cherry picked from commit 26bbf12e)