Implemented Polling#doClose

lib/transports/polling.js

@@ -203,11 +203,23 @@ Polling.prototype.write = function (data) {
 };
 
 /**
- * Writes a payload of messages
+ * Closes the transport.
  *
  * @api private
  */
 
-HTTPTransport.prototype.payload = function (msgs) {
-  this.write(parser.encodePayload(msgs));
+Polling.prototype.doClose = function () {
+  if (this.dataReq) {
+    debug('aborting ongoing data request');
+    this.dataReq.abort();
+  }
+
+  if (this.req) {
+    debug('cleaning up ongoing poll');
+    this.send({ type: 'close' });
+  } else {
+    // upon next poll an error 500 will be emitted
+    // which is effective at signaling the close
+    debug('closed polling but no open request - next poll should err');
+  }
 };