Change record status: 
Project: 
Introduced in branch: 
8.0.x
Introduced in version: 
8.0.x
Description: 

This change record should be removed as the commit was reverted.

The MapItem field type class was introduced for Shortcut functionality in #2021779: Decouple shortcuts from menu links, and then made unused in #2235457: Use link field for shortcut entity. It was never properly documented or tested, and is not currently used in Core. It also has no formatter or widget.

So, it was really dead code, and in #2563843: MapItem is broken for configurable fields this class was removed. Full namespace is:

\Drupal\Core\Field\Plugin\Field\FieldType\MapItem

Impacts: 
Module developers
Updates Done (doc team, etc.)
Online documentation: 
Not done
Theming guide: 
Not done
Module developer documentation: 
Not done
Examples project: 
Not done
Coder Review: 
Not done
Coder Upgrade: 
Not done
Other: 
Other updates done