Web Content - buttons not working after changing language and adding repeatable row

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 6.0.X EE
• Fix Version/s: 6.0.X EE
• Component/s: WCM, WCM > Web Content Administration
• Labels:
  • QA-R
  • QA-TP
  • ee-ts
• Environment: LIFERAY VERSION: 6.0 SP2 ; OPERATING SYSTEM: Windows Server 2008; APPLICATION SERVER: JBoss 5.1 EAP ; JAVA VIRTUAL MACHINE: Java 6; DATABASE: SQL Server 2008
• Branch Version/s:
  6.0.x
• Backported to Branch:
  Committed
• Story Points: 2
• Fix Priority: 3

Steps to reproduce :
1. Go to Control Panel -> Web Content
2. Add a web content with a structure that has repeatable row element(HTML Text Area)
3. Publish this web content
4. Edit this web content again
5. Change to another language, and then click on the "+" button to add repeatable row
6. Now click on buttons(Save as Draft, Publish, Preview, Download). You'll find them not working.
No error appears in log.

Notes :
Able to reproduce on 6.0.x(146842), fixed on trunk(Git ID:a0e9b381b1fb6720ff9cb0c0fbfa1aac8a3d63b8).