The TQ Pacer schedules delayed task according to target time of
PacingController. It drains all valid ProcessPackets() in single loop,
denies retired scheduled tasks, and round up the timeout to 1ms.
This CL also improves packet size estimation in TQ Pacer by removing
zero initialization, and introduces `include_overhead_` configuration.
Tests:
1. webrtc_perf_tests: MaybeProcessPackets() calls
2075147 -> 2007995
2. module_unittests: MaybeProcessPackets() calls
203393 -> 183563
3. peerconnection_unittests: MaybeProcessPackets() calls
66713-> 64333
Bug: webrtc:13417, webrtc:13437
Change-Id: I18eb0a36dbe063c606b1f27014df74a65ebfc486
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/242962
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36179}