Howto move a Plone control panel from z3c.form to plone.app.registry

z3cform-p.a.controlpanel

1) Move the Interface (e.g. ISecuritySchema) from z3cfrom-p.a.controlpanel branch into CMFPlone/interfaces/controlpanel.py: 

   - Code: https://github.com/plone/plone.app.controlpanel/blob/plip10359-z3cform/plone/app/controlpanel/interfaces.py#L430
     (make sure the added interface is listen in P.CMFPlone/../profiles/dependencies/registry.xml)
   - Tests: Copy https://github.com/plone/Products.CMFPlone/blob/master/Products/CMFPlone/controlpanel/tests/test_controlpanel_site.py and amend it

   to test the settings in the interface. Do not directly copy the test from
   the z3cform-p.a.controlpanel branch: https://github.com/plone/plone.app.controlpanel/blob/plip10359-z3cform/plone/app/controlpanel/tests/test_security.py
   
  If you run into "KeyError: 'Interface `Products.CMFPlone.interfaces.controlpanel.IFilterSchema` defines a field `stripped_tags`, for which there is no record.'", make sure all registry lookups use prefix="plone" and that the ControlPanelForm has the schema_prefix="plone" attribute.
 

2) Move control panel browser view: 

   - Code: Copy browser view from z3cform-p.a.controlpanel branch: https://github.com/plone/plone.app.controlpanel/blob/plip10359-z3cform/plone/app/controlpanel/browser/security.py

   - Test: Copy https://github.com/plone/Products.CMFPlone/blob/master/Products/CMFPlone/controlpanel/tests/test_controlpanel_browser_site.py and amend it to the settings.

3) Move BBB Adapter: 

   - Code: https://github.com/plone/Products.CMFPlone/blob/master/Products/CMFPlone/controlpanel/bbb/site.py and amend it to the settings. Do not directly copy over https://github.com/plone/plone.app.controlpanel/blob/plip10359-z3cform/plone/app/controlpanel/bbb/security.py.

   - Test: Copy https://github.com/plone/Products.CMFPlone/blob/master/Products/CMFPlone/controlpanel/tests/test_controlpanel_bbb_site_adapter.py and amend it to the settings.

4) Write a robot test like:
   https://github.com/plone/Products.CMFPlone/blob/master/Products/CMFPlone/tests/robot/test_controlpanel_search.robot. Make sure that the tests actually tests the real changes in the Plone site. This will make you find the code parts for 5).

5) Replace the CMFPlone/plone.app.layout portal_properties lookups with
   plone.app.registry lookups.

6) Write upgrade step to migrate old control panel setting to the new p.a.registry: https://github.com/plone/plone.app.upgrade/blob/master/plone/app/upgrade/v50/alphas.py#L280

7) Check commits to plone.app.controlpanel in the last year to make sure we
   include all the latest changes.