Merge "Better error message in case of multiple splits." into udc-dev am: 413bb027

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23179125



Change-Id: Ic7e43cac4cc37b04defb316e6849fc2c99cbee4d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>