The dropdown panel shouldn't be shown when the Dropdown fragment with Keep Panel Open in Edit Mode is inherited from master

• Type: Impedibug
• Status: Closed
• Priority: Major
• Resolution: Completed
• Affects Version/s: Master
• Fix Version/s: 7.4.13 DXP GA1, Master
• Component/s: Navigation Menus, Out of the box Fragments > Navigation Menu
• Labels: None
• Git Pull Request: https://github.com/liferay-echo/liferay-portal/pull/3248

Step to reproduce:

1. Add a new site
2. Add a master page
3. Add a Dropdown fragment above the Drop Zone
4. Click the body of Dropzone fragment > General tab
5. Check the Keep Panel Open in Edit Mode
6. Add a Menu Display fragment into dropzone of Dropdown fragment
7. Assert the Menu Display is shown in dropzone panel
8. Publish Master
9. Add a page based on master page

Expected Results:
The dropdown panel should be collapsed.

Actual Results:
The dropdown panel is shown. However, there is no way to add fragments to dropdown panel in content page.

Reproduced on:
Tomcat 9.0.37 + MySQL 5.7. Portal master GIT ID: dcd5d34ba6925c546570aef81055d7a5412b1c5a.