Temporarily always enable dexlayout output verification.

Enable the IR-level check by default for debugging b/62840842.
Will ensure that output of dexlayout is valid.

Bug: 62840842
Test: mm test-art-host

(cherry-picked from commit 0f153002)

Change-Id: I945c880ca5d0bc89e31eb7269d681f3a25f19670