Merge "Add a device config namespace for battery_stats" into udc-dev am: 01d61c38 am: fa036a91

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



Change-Id: I6d67cfa285ace718d163825a53a402e64176a295
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>