Merge "Let notification shade control system bar visibility" into tm-qpr-dev...

Merge "Let notification shade control system bar visibility" into tm-qpr-dev am: a71f02fb am: c7e4c899

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19622684



Change-Id: I1a91beeef44a96607571b5097e7438d32e7ec678
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>