[automerger skipped] Make CentralSurfaces an Interface. am: ee483863 am: 2e9d6f75 -s ours

am skip reason: Merged-In Iab41b70e0c65d75560010d961dcb52a11fd237f5 with SHA-1 ee483863 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17756836



Change-Id: Ia3f35699eb247ba9a2b1393c2a7fc9b173211c75
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>