Merge changes from topics "android-os-connectivity-wifiactivityenergyinfo", "requestactivityinfo"

* changes:
  Move WifiActivityEnergyInfo to android.os.connectivity
  BatteryStats: Move WifiActivityEnergyInfo to android.os.connectivity
  Statsd: Move WifiActivityEnergyInfo to android.os.connectivity
  Formalize WifiManager#requestActivityInfo as @SystemApi
  BatteryStats: Formalize WifiManager#requestActivityInfo
  Statsd: Formalize WifiManager#requestActivityInfo