Merge "Log each time the layer stack changes for DisplayDevice." into tm-qpr-dev am: 81a111d85c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21601972

Change-Id: I20779ec50d76430104aa8b40c69016c220fc1418
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>