Merge "power/stats: Return exception codes on error" am: 777542355a am: 3dd0588218 am: 4abdf481ec am: 40fc1224b2

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1626963

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I767e1d9ba3b158f99aec85bcafb0764eb4b1eafa