Fix null dereference in SweepInterpreterCaches am: 6a05d70393 am: 731076f33b am: 27deab460b am: 92d2450a91

Original change: https://android-review.googlesource.com/c/platform/art/+/2194755

Change-Id: Iec43bdccc65216c231a97a6883b8505148dbf9ea
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>