Listen for foreground AppOps changes

Change AudioPolicyService to listen to AppOps changes including
foreground mode changes, so we appropriately silence backgrounded apps
with opened AudioRecords.

Bug: 247768581
Fixes: 268724205
Test: AudioRecordTest
Test: OboeTester (non mmap) record silenced when backgrounded - 6s
Change-Id: I3bdcb76876c479d432201e4bb03cdbf35d877909
1 file changed