Windows detection

[JamesNK]

Does this dotnet/extensions#424 issue apply to these places: https://github.com/aspnet/SignalR/search?q=Environment.OSVersion.Version&type=Code

[muratg]

This is a test enhancement. It won't block 2.2.

edit: Thanks @JamesNK for correcting me below.

[JamesNK]

It is also used by the .NET client to determine whether the client supports websockets -

SignalR/src/Microsoft.AspNetCore.Http.Connections.Client/HttpConnection.cs

Lines 574 to 592 in 78a0a68

	private static bool IsWebSocketsSupported()
	{
	#if NETCOREAPP2_2
	// .NET Core 2.1 and above has a managed implementation
	return true;
	#else
	var isWindows = RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
	if (!isWindows)
	{
	// Assume other OSes have websockets
	return true;
	}
	else
	{
	// Windows 8 and above has websockets
	return Environment.OSVersion.Version >= Windows8Version;
	}
	#endif
	}

[analogrelay]

Take a quick look at this @BrennanConroy in case we need to make this change in our prod code.

[analogrelay]

I took a look and we should be OK. The problem is that OS Version gets fuzzy between Windows 8 and Windows 10. However, we just need to be able to detect we're on at least Windows 8, which we are able to do.

I'm comfortable closing this until we hear customer feedback that there's an issue here.