Merge "[flexiglass] Implementation of the Shade scene UI." into udc-qpr-dev am: 026dfde8

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24079089



Change-Id: I330b6a0922736b944e17c17d5f4a0011cdae741a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>