Cannot edit WC with child structure after upgrade to 7.1

• Type: Bug
• Status: Closed
• Resolution: No Longer Reproducible
• Affects Version/s: 7.1.0 Beta 2, Master
• Fix Version/s: 7.1.X, Master
• Component/s: Dynamic Data Mapping > Upgrades
• Labels:
  • 7.1-should
  • profiq
• Fix Priority: 5

Steps to reproduce:

1. In version 6.1
2. Create parent structure contains text, DM, repeatable image, text box with nested boolean
3. Create child structure, extends parent structure, contains select list with no options
4. Create template for child structure
5. Create web content with child structure
6. Upgrade to 7.1
7. Try to edit web content, form will be locked
8. Try to edit default values for child structure, form will be locked
9. Try to add new web content with child structure, form will be locked

Actual Result >
Form is locked, looks like loading
Content of inputs cannot be edited

Error in browser: "Uncaught TypeError: Cannot read property 'unshift' of undefined"

Expected Result >
Data should be editable in form

Priority L4 + S4 = 5 

Reproducible:
Chromium 66
Upgraded from: Liferay 6.1 EE, Oracle 12c
To: Liferay 7.1 beta 2, Oracle 12c
via portal-tools-db-upgrade-client tool