Exceptions in data_received() (while using @stream_request_body) are not handled properly

To overcome that, I use:

@stream_request_body
class RestoreHandler(RequestHandler):
    ...
    @gen.coroutine
    def data_received(self, chunk):
        try:
            yield buggy_operation()
        except Exception:
            self.set_header('Connection', 'close')
            self.set_status(413, 'Upload aborted')
            self.finish()
    ...

If I do not catch exception, connection silently aborted (as browser said). But instead, Tornado should respond with HTTP response and close connection.

Start by tracing Tornado's @stream_request_body handling and the data_received() exception path, then reproduce the behavior with the provided RestoreHandler example. Done means an uncaught exception during streamed request processing produces an HTTP response and closes the connection instead of silently aborting it.