Merge "Fix NPE in TTS service if no engine string" into udc-qpr-dev am: a3f36b1e

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24758913



Change-Id: I16a4dafb0c2a3f6828102d51723f0f1d2f80e2d2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>