This updates DataChannelController and test classes to use
GetSctpSslRole_n instead and query the role on the network thread.
Along the way this CL makes the init config struct for when constructing
data channels, mandatory. It's now passed via const& instead of by pointer. In practice a valid pointer was always being passed.
Bug: webrtc:11547
Change-Id: I0f4bbf364969cc2dec07871c297ddbef0c175f86
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/298307
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39676}
335d084b3b