'Multiple' option in Forms Select field does not save

• Type: Regression Bug
• Status: Closed
• Resolution: No Longer Reproducible
• Affects Version/s: 7.0.0 Alpha 3
• Fix Version/s: 7.0.0 Alpha 3
• Component/s: Forms
• Labels: None
• Fix Priority: 3
• Sprint: Sprint 4: Nov, 09 - Nov, 20

Steps to reproduce:

1. Go to Admin > Forms
2. Add a form with Select field
3. Go to Advanced Settings of field > Turn on Multiple option
4. Save field
5. Before saving the Form, go back into the Settings of the added Select field
6. Assert that the Multiple option is still on
7. Save Form
8. Go to Admin > Forms
9. Edit Form created
10. Go into the settings of the Select field
11. Assert that the Multiple field is still turned on

Expected Result:
The selected options persists and the Multiple option is still turned on.

Actual Result:
The selected option for the Multiple option does not persist and the option is not saved. Refer to attached gif.

Reproduced on:
Tomcat 7.0.62 + MYSQL 5.6.27
Portal master GIT ID c5dd3793559b32d707d92461cec55c8b6c31cf6c