Merge "[Partial Screen Sharing] Dismiss background after app selector...

Merge "[Partial Screen Sharing] Dismiss background after app selector launched" into udc-qpr-dev am: db448b38

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24025610



Change-Id: I4807798d6b75f8c9d5287566e439e9e26939c8a1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>