Merge "Isolate count of visible window from mirror of uid state" into sc-v2-dev am: e55e1952c0 am: 4641fb4e28

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17135563

Change-Id: I9a190c709c6464b735d5c0a4bcadc5dae3a84b4f