Merge "Fix NPE in TTS service if no engine string" into udc-dev am: 987b2e7d am: 2b4d5f16

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



Change-Id: Ifb40e521b27b8a76b00a1f53d82325f0cba1a96e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>