This adds an optional callback closure and an enum representing the error. Bug: webrtc:390314937 Change-Id: If9a22dd6d90d5c4d94175e021511766ea49acec2 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/374420 Commit-Queue: Peter Hanspers <peterhanspers@webrtc.org> Reviewed-by: Jakob Ivarsson <jakobi@webrtc.org> Cr-Commit-Position: refs/heads/main@{#43780}