Reverse proxy returns 500 on ERROR_WINHTTP_INVALID_SERVER_RESPONSE

[qrli]

When ERROR_WINHTTP_INVALID_SERVER_RESPONSE (we found in SF logs) happens to SF reverse proxy, it returns 500 instead of 502, which is misleading.

SF log sample:
ca41421c-9691-40f0-9884-b2c5c6078784 Error while forwarding request to service: request url = https://xxx:19008/xxx/xxx/xxx/xxx, verb = GET, remote (client) address = 10.0.1.11, request processing start time = 2019-11-08T08:17:58.4864421Z, forward url = http://10.0.14.6:33604/xxx/xxx, response status code = 500, description = Internal Server Error, phase = FinishSendRequest, internal error = ERROR_WINHTTP_INVALID_SERVER_RESPONSE

We observe many such errors with recent Node.js versions. Looks related to this issue.

Expected Behavior

It should return 502.

Current Behavior

It returns 500 confusingly, as we never expected a reverse proxy to produce 500 by itself.

Steps to Reproduce

Host a Node.js web server in SF and access via reverse proxy.
A small percentage of requests will hit this issue. Node v10.15.* has higher rate.

Context (Environment)

Azure Service Fabric

Service Fabric Runtime and SDK Version :

Operating System :

Windows

Cluster Size :

Possible Workaround