Merge "Fix Letterboxing for Transparent Activities" into tm-qpr-dev am: 86c6d900 am: 0a737b0a

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20139788



Change-Id: I14a8b73c2d7156b66c833809cdae4b831db5b15b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>