(DO NOT MERGE) Battery monitoring fixes:

- Improve monitoring of level changes to not be confused
  when it goes up while draining or down while charging.
- Put back in connectivity service code to tell battery
  stats about the interfaces.
- Turn back on reporting of mobile radio active state
  from the RIL.
- Fix bug in marshalling/unmarshalling that would cause
  the UI to show bad data.

Change-Id: I733ef52702894cca81a0813eccdfc1023e546fce