Poison dead objects only in debug build am: 020c72a87a am: a76d672ca9 am: 4cff5d9b16

Original change: https://android-review.googlesource.com/c/platform/art/+/2289433

Change-Id: I0d8c4a8eeb54f828abdf774eaea41df671d6cca1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>