Merge "[pm] fix potential NPE in system server" into udc-dev am: e6ce51f3 am: 96f1ec21

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23539105



Change-Id: I0c952e5283e9386d508242e2b216a3b256369e13
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>