'If the return value of the decorated function is an instance of
L{EndpointResponse} with headers specified then the response
generated includes those headers.'

@validateLogging(_assertRequestLogged('/foo/explicitresponseheaders'))
def test_explicitResponseObjectWithHeaders(self, logger):

    application = self.application(logger, {})
    request = dummyRequest('GET', '/foo/explicitresponseheaders', Headers(), '')
    self.render(application.app.resource(), request)
    response = asResponse(request)
    self.assertEqual(response.headers.getRawHeaders('x-key'), ['value'])
