Initial implementation of batch scan throttling.

1. Wait for longer interval when there are no results
2. Increase interval when the screen is off
3. Increase interval for unfiltered clients.

go/batch-scan-optimization

Bug: 366559598
Bug: 392132489
Flag: batch_scan_optimization
Test: atest ScanControllerTest
Change-Id: I1fce8d32da6c047611ab98a9a71f07533e003c50