Pull Request for Issue #16421

Summary of Changes

Adding conditionals to display the default placeholder with null value defined in the field Option

Testing Instructions

Edit an item which contains a choice for a menu item field using the modal_menu type.

1. Creating a Menu Item Alias. Choosing the menu item to alias to.
2. Creating a Create Article menu item. Choosing the menu item Submission Redirect in Options.
3. Creating a Login Form menu item. Choosing the Menu Item Login Redirect and Menu Item Logout Redirect in the Options.
4. Creating a Logout menu item. Choosing the Logout Redirection Page in the Options.
5. Editing the Site Login Form module. Choosing the Login Redirection Page and the Logout Redirection Page.
6. Editing the Site Menu module. Choosing the Base Item.

The xml code for the Menu module is for example

				<field
					name="base"
					type="modal_menu"
					label="MOD_MENU_FIELD_ACTIVE_LABEL"
					description="MOD_MENU_FIELD_ACTIVE_DESC"
					select="true"
					new="true"
					edit="true"
					clear="true"
					>
					<option value="">JCURRENT</option>
				</field>

In each case, select a menu item in the modal. Then Clear that menu item.

Expected result for the placeholder value

1. Select a Menu Item
2. Default
3. Default for both
4. Default
5. Default for both
6. Current

Actual result

All have Select a Menu Item

Patch and test again. Do not forget to choose a menu item and Clear to confirm that the correct value is displayed.

Here is an example —after patch— concerning the original issue with Menu module.

@epidote