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

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

Change-Id: Ic8174fd2996d54257c706c6eac99d980de78e0af
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>