Merge "Define new letterbox background color" into tm-qpr-dev am: 977b4b94

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20280444



Change-Id: I6d8faab33a25241a021223b5b3b3789a3d601134
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>