Merge "Null check when force navigation bar true and on lockscreen." into...

Merge "Null check when force navigation bar true and on lockscreen." into tm-dev am: 3e2a850f am: 2187f9df

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17054378

Change-Id: If36d4f893789752e0254a4e33ac781c968820f54