Revert "Report brightness event to StatsLog"

This reverts commit d5cdb61d.

Reason for revert: b/269556535

Also, this accesses locked structures without holding the lock in an unsafe way.

Bug: b/269556535
Test: build success
Change-Id: I3a6d3e62d4418cb10199f569d6d750396a51443e
Merged-In: I3a6d3e62d4418cb10199f569d6d750396a51443e