API: Spread autoblocks from action=edit and action=move

API: Spread autoblocks from action=edit and action=move

The code in EditPage and SpecialMovepage does this primarily in web UI
code paths that aren't called by the API. EditPage also has a check in
the internal code path used by the API, but ApiEditPage runs its own
permissions check first and won't reach that code path.

Bug: T216245
Change-Id: I6263c8b60a24f3195dba583463f1ce4b004f82f5