Merge "[1/n] Add build and runtime flags for fullscreen option" into udc-qpr-dev am: c2ec3a5a55

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24176523

Change-Id: Icfdfd29f0a4e15e3e5b2d3d9fe360b5e4d4c8218
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>