Align Reject with Ack/Nack

[danielmarbach]

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See #1413 (comment)

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[lukebakken]

Good catch

[Tornhoof]

I wonder if the split between ValueTask and Task makes sense at all here, I could not really find any async methods doing the

if(valueTask.IsCompletedSuccessfully) 
{
  return FastPath();
}
else 
{
  return SlowAwaitPath();
}

dance, or anything in a really tight loop where the above should be used.

[danielmarbach]

@Tornhoof I commented on the umbrella issue that I'm not sure if the valuetask vs task has further been thought through. Currently the entire Channel -> Session -> Connection -> Frame -> ChannelWriter exposes the underlying channelwriter value task and that is a choice that I think is fine. What is confusing right now is that are public APIs that are essentially doing ValueTask all the way through the hierarchy while others don't.

This PR does at least align the methods that call into ModelSendAsync

[danielmarbach]

For example I also do not understand why when WriteAsync on the framehandler is returning a value task the corresponding SendProtocolHeaderAsync is not

[lukebakken]

What is confusing right now is that are public APIs that are essentially doing ValueTask all the way through the hierarchy while others don't.

If there are other changes you suggest, feel free to point them out and I'll take a look, or open new PRs.

It has been a while since I looked at this in detail, but I remember trying to avoid conversion from ValueTask -> Task.

[lukebakken]

For example I also do not understand why when WriteAsync on the framehandler is returning a value task the corresponding SendProtocolHeaderAsync is not

There's no good reason that I can see! Feel free to make a list and I can address this. I'll open an issue to track this.

UPDATE: #1645