Merge "Do not letterbox the activity in PiP mode" into udc-dev am: 41667fa9...

Merge "Do not letterbox the activity in PiP mode" into udc-dev am: 41667fa9 am: 3b341fdb am: d7fb275b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23503609



Change-Id: I7d27ee67c02ce7454c5d21c6c19e692947bd555d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>