Description of problem:

If we have a process that has a swimlane, inside this swimlane we have a subprocess and then a few elements (task, connectors, etc), once we have save it and reopen the process, the elements are all messes and not in the swimlane subprocess.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
1. Create a new process
2. Add a swimlane to it
3. To the swimlane, add a new embedded subprocess
4. add a new elements to the subprocess, such as a starting node, a human task and an ending node;
5. Connect the subprocess to the original starting node and the output of the subprocess to a ending node;
6. Save the process and reopen it;

Actual results:

The elements will show up in a messed way and outside of the subprocess

Expected results:

The elements should be all organized.

Additional info:

You can find attached screenshots of before and after, showing the issue.