Merge "Toggle dim according to progress of recents animation" into udc-dev am:...

Merge "Toggle dim according to progress of recents animation" into udc-dev am: f51e5001 am: 20622b97 am: 3d3cf5a6 am: ca97932f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23693824



Change-Id: Iadcb20504e84a136927115b3411ba80859f01fdd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>