RetryDelegatingHandler breaking change between Microsoft.Rest.ClientRuntime.2.3.12 and Microsoft.Rest.ClientRuntime.2.3.15

[saguiitay]

In Microsoft.Rest.ClientRuntime.2.3.12, when you create a new RetryDelegatingHandler using the default CTOR, everything worked fine, and you could then assign the InnerHandler (which is of type HttpMessageHandler):

var handler = new RetryDelegatingHandler();
handler.RetryPolicy = retryPolicy;
handler.InnerHandler = new WebRequestHandler();

In Microsoft.Rest.ClientRuntime.2.3.15, this results in an ArgumentNullException, and you much provide a DelegatingHandler instance yourself. Notice, that since the CTOR requires a DelegatingHandler, you can't pass an WebRequestHandler instance like I did in the above code, and I now need to jump thru some hoops:

var handler = new RetryDelegatingHandler(retryPolicy, new SendableHandler(new WebRequestHandler()));

private class SendableHandler : DelegatingHandler
{
    public SendableHandler(HttpMessageHandler innerHandler) : base(innerHandler) { }

    public new Task<HttpResponseMessage> SendAsync(
        HttpRequestMessage request,
        CancellationToken cancellationToken)
    {
        return base.SendAsync(request, cancellationToken);
    }
}

[shahabhijeet]

@saguiitay we will have an update most probably today.
Will update this issue once I publish the fix.

[shahabhijeet]

New ClientRuntime has been published with the fix #4906