Merge "Add dark scrim from a background thread during unfold" into tm-qpr-dev...

Merge "Add dark scrim from a background thread during unfold" into tm-qpr-dev am: d1783ae8 am: e4f61e1e

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20437905



Change-Id: Iec36f3bee1d915078bc102c815e7aec4b85fb24c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>