Merge "Add a shared library for setting flags in SysUI." into sc-v2-dev am: fdb01b6353 am: abef1d3d2b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16092692

Change-Id: I2debaf6ed83b2cbf72bbb1b578c8b30a8a58a4da