Phone service state change atom.

Background: BatteryStatsService tracks the phone scanning time metric. In Q,
we are migrating the dumpsys-based collection to the new infra. This CL is to
instrument the new logging mechanism.

Test: statsd test
FIX: b/116748990

Change-Id: I3cf5e0026bfc6f594c5f7b524f14b3a43b702afb
6 files changed