[RESTRICT AUTOMERGE] AccessibilityManagerService: remove uninstalled services from enabled list after service update. am: 766911c331 am: 2229cd9dd9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/26709088

Change-Id: Id50ebe9f0f9924c218613c85f6adee23945afed2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>