Note:
* PLR is calculated over all of the known packets.
* RPLR is calculated over all of the known packet *pairs*. That is, only over sets of subsequent packets where the reception status is known for both.
BUG=webrtc:7058
Review-Url: https://codereview.webrtc.org/2629883003
Cr-Commit-Position: refs/heads/master@{#16401}