Merge "[wm] fix npe when removing trusted task overlays" into udc-qpr-dev am:...

Merge "[wm] fix npe when removing trusted task overlays" into udc-qpr-dev am: b6a07bea am: d9d0c2a8

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23481001



Change-Id: Icb5e45e54542145c68f94d153b5eddb2ae9daa5c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>