Attachment indexing in cluster mode

There is an issue with attachment indexing in cluster mode. When an attachment is added from one node the other node are not indexing the attachment. The same thing with standard pages is working.

Test case:

1/ Create a page with content
2/ Wait for 20 seconds and verify that it's searchable from all nodes. It is.
3/ Attach a file to it (text file)
4/ Wait for 20 seconds and verify that it's searchable from all notes. It is not. Only the node where you attached the file has indexed the attachment.