Merge "Allowing activity visible behind translucent adjacent TaskFragments" into sc-v2-dev am: 9d25f3fbe8 am: a2166f121b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16128727

Change-Id: I49dd14cac185c3dc2fcaeeae6211ae28d0583645