Merge "Merge "Revert "Allow bar to be transparent if letterbox contains bar""...

Merge "Merge "Revert "Allow bar to be transparent if letterbox contains bar"" into rvc-dev am: 64682e76 am: 6ddc9881" into rvc-d1-dev-plus-aosp am: c6920dd9 am: 9756bb03

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/12128053

Change-Id: Ie4795c173ad50213966051576d42bde40340fc6d