Merge "Add null checking when deleting hotword detectors" into udc-dev am: c3b7d1b2

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23380616



Change-Id: I25bda0fed3a32e78fd3c790721e390ce97f6aaa2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>