Merge "Implement dream out overlay transition" into tm-qpr-dev am: 620f597dd4 am: ffec20f8a3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20377749

Change-Id: Ie79aedb6e89361178129dc40a5fa0cbcb353e1b3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>