[statsd] LogEventFilter refactoring

- extracted separate interface AtomsInUseChangeListener
- allows more flexible control to handle atom in use changes
- plan to support multiple listeners (socket vs file) which
  might require different logic implemented

Flag: EXEMPT refactoring
Bug: 407064406
Test: statsd_test
Test: atest GtsStatsdHostTestCases:com.google.android.statsd.gts.StatsdHostTestCases.testPushedAtomsLoggingControl
Change-Id: I490a38952425980d73bca5383d2f6b6abd97526e
19 files changed