Merge "Fix NPE in TTS service if no engine string" into udc-dev am: 987b2e7d35 am: 2b4d5f1673 am: 9b147656de

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24758914

Change-Id: Iebd19a5bdabc0f70f42a0e097f60f6efccdac4d3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>