Merge "Fix the blank PiP window when unlock" into tm-dev am: 6e086786 am: c29f9a56

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18203211



Change-Id: I595a881a8bbe60d8f99a3f9698dd3c2cbb2d5acd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>