This is similar to the field trial parser but it uses a normal struct
with normal fields as underlying storage. This makes it easier to
understand and use as only the encoding and parsing uses non-
standard constructs. Additionally, it makes it easier to use the
struct as a regular config struct when the values are not set
using field trials.
Bug: webrtc:9883
Change-Id: I5b16c2a71875b6f478383decff18fbaa62bc404a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/145203
Reviewed-by: Jonas Olsson <jonasolsson@webrtc.org>
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28810}
