Expect/continue not working for HttpRequest objects that are implemented with an HttpRequestWrapper

Certain sorts of requests (multipart post being one of them) use HttpRequestWrapper internally to wrap the original request. But the Expect/Continue processor has this check in it:

            if (request instanceof HttpEntityEnclosingRequest) {

That effectively disables expect/continue for all wrapped requests, since HttpRequestWrapper is not derived from HttpEntityEnclosingRequest.

Suggestion: A better way to structure this would be to have a method in HttpRequest that the expect/continue processor would call, instead of doing an explicit instanceof class check.