ping response protocol

#### Investigative information

Please provide the following:

- Timestamp: ongoing
- Function App version (1.0 or 2.0-beta): both versions
- Function App name: hml-products-cs-dii (or other apps being pinged by the scale controller experiencing this exception)
- Region: all

#### Repro steps

Provide the steps required to reproduce the problem:

Issue started with 6/19 release
Not sure how to repro, it might just be on unhealthy apps. I found a symptomatic app and rdp'd to the worker to investigate. Using netmon, i found that pings to the root of the site were returning "Host is not running" or some such message. This causes a protocol exception with the 204 http status code in the scale controller.
from NetMon: "HTTPPayloadLine: Function host is not running."

#### Expected behavior

Provide a description of the expected behavior.

There should be no http response with a 204 status code.

#### Actual behavior

Provide a description of the actual behavior observed.

from NetMon: "HTTPPayloadLine: Function host is not running."

#### Known workarounds

Provide a description of any known workarounds.

This isnt "broken" the ping still gets through. It just causes thousands and thousands of errors in the scale controller

The issue does not identify a source file, test, or code entry point. Start by tracing the scale controller's ping handling and the Function host response described in the NetMon output, using an unhealthy app if it can be reproduced. Done means the ping still reaches the app without a 204 response or protocol exceptions.

Written by the indexing model from the issue text.