Merge "Fixes @Nullable issues SystemUI-tests" into udc-qpr-dev am: a12441e8f9 am: cd4c5b944e

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24409471

Change-Id: I513df984b2b30a11f14c2f7a29353076e9840786
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>