Change record status: 
Project: 
Introduced in branch: 
8.x
Introduced in version: 
8.x-alpha4
Description: 

In previous 8.x releases, \Drupal\system\SystemConfigFormBase lived in system module. Because this is a general class useful outside of system module, it has been relocated to \Drupal\Core\Form\ConfigFormBase instead.

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