[Question] Support for non-json content-type header

HI newbie here,

I'm using chalice for converting legacy api to serverless framework for REST and SOAP(backward compatibility). I converted the SOAP payload to JSON by following the steps from this [link](https://github.com/mwittenbols/How-to-use-Lambda-and-API-Gateway-to-consume-XML-instead-of-JSON). However, I have received "InternalServerError" with "Unknown Request". It looks like the resource_path/context was messed up when APIGateway was reconfigured. I'm thinking of creating a pure lambda and attached to a reconfigured API-Gateway. Is there any other work-around I can do?

Start by comparing Chalice's handling of resource_path and request context with the reconfigured API Gateway and the linked XML-to-JSON setup. Reproduce the InternalServerError using the non-JSON content type; done means determining whether Chalice supports this configuration or documenting a supported workaround.

Written by the indexing model from the issue text.