Merge "Add listeners for the creation and destruction of virtual displays. This will be used later by VibrationSettings to keep record of active virtual displays." into tm-qpr-dev am: 81b40bae am: 09e2a7f9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19477752



Change-Id: If97536e1b889be899966529215695e12750e2c57
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>