User generated headers in http responses are not logged

If an HTTP Servlet adds headers by using httpServletResponse.addHeader or httpServletResponse.setHeader these headers are not logged by the LoggingOutInterceptor.

This is because DefaultLogEventMapper::getHeaders only logs headers from the message's "Message.PROTOCOL_HEADERS" field rather than the headers from the HttpServletResponse in the Message's "HTTP.RESPONSE" field.

As far as I can tell the "Message.PROTOCOL_HEADERS" are merged into the response's headers by Headers::copyToResponse.

So If the Message has an "HTTP.RESPONSE" field it should be safe to only log the headers from that.