Merge "Add support for onReject and onError for external hotword." into tm-dev am: 90579f32

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18308197



Change-Id: I5d2c9717cb060f0df54dac78fae56f3614a29405
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>