Add HearingDeviceActiveEventReported atom

atom tester: https://data.corp.google.com/android/test/atoms?preset=specified

Flag: EXEMPT metric only
Test: build pass and test with atom tester
Bug: 394465992
Merged-In: I775aa6171d4350d511c8683bc3c1bc372dec4866
Change-Id: I775aa6171d4350d511c8683bc3c1bc372dec4866
2 files changed
tree: 97b5591bd956f3427e0e9a7cb8c8d6f5cbfee38f
  1. stats/
  2. OWNERS