[automerger skipped] Merge "Fixes @Nullable issues in System UI and WMShell."...

[automerger skipped] Merge "Fixes @Nullable issues in System UI and WMShell." into udc-d1-dev-plus-aosp am: e10c64a3 -s ours am: 34784897 -s ours

am skip reason: Merged-In I74cc61fd87819be7302590d788c3c230bff57544 with SHA-1 507e0b7b is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24692799



Change-Id: I372eb15c592f8252ecfaafb597c658029b36ed60
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>