Merge "Show letterbox rounded corners behind navbar" into tm-qpr-dev am: 6f20d51b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20882605



Change-Id: I280417578f5f6b0b19a6caa1c3156e8cb7386da3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>