Validate input of JNI::NewStringUTF(). am: 8c66531772

Original change: https://googleplex-android-review.googlesource.com/c/platform/art/+/13137935

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Iaebaf31f8d00c1ca1a88b98f1bdc1237fcbb2222