Merge "Fix potential NPE in STHelper" into udc-dev am: c27813eb am: 3b1b4010

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23075100



Change-Id: I16d13030e5799f1cc15d9e3088c8e775c5d8d2c6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>