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

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



Change-Id: I88da4ff0224999f3936f31fd82353f619e43ac31
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>