filtering out the -1 value as it is done for "legacy" stats.
Also change the protocol and don't use "udp" and "tcp" which are misleading since the datachannel protocol is user-supplied.
BUG=webrtc:15071
Change-Id: I45d735fcf30144969630f5b8a91b40f12585bbfd
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/300483
Commit-Queue: Philipp Hancke <phancke@microsoft.com>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40333}
423faa6067