This CL adds seperate counters for ANA frame length increases and decreases, which gives more insight into what actions are taken. In addition, a new stat is added to track the sum of the uplink packet loss fraction that is set by the ANA FEC controller.
BUG=webrtc:8127
Review-Url: https://codereview.webrtc.org/3007243002
Cr-Commit-Position: refs/heads/master@{#19756}