Merge "Add a scrim to taskbar for bubbles expanded state" into sc-v2-dev am: 20c05fbd4c am: 228537ec0b

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15910463

Change-Id: I0a76e9d33c2617d6708b72458c013ddc2b448428