Merge "Revert "Allow bar to be transparent if letterbox contains bar"" into rvc-dev am: 64682e76f2 am: 6ddc9881ae

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

Change-Id: I790baf429ae137b3ac117756cc701e8ea057a1f8