Merge "Add a device config namespace for battery_stats" into udc-dev am: 01d61c38

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21780255



Change-Id: Ibef7d684898e425a19198cdbf57ab7eab9c6e93c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>