Problem/Motivation
In #1812866: Rebuild the server side AJAX API a new Object-Oriented AJAX API for D8 was introduced. The existing D7 Ajax API was left in place while usage was converted from the old to the new. It's time to remove the D7 Ajax code from Drupal.
Proposed resolution
Remove most of the contents of ajax.inc. Rewrite / remove any remaining usages of ajax_command_*, ajax_render, or any other Ajax functions removed from ajax.inc.
Remaining tasks
- Remove any remaining calls to ajax_render().
- "fix AjaxEnhancer, which was doing things the old backward way" - Crell
- Test XHR2 and iframe uploads across browsers
Related Issues
#1812866: Rebuild the server side AJAX API
#1938980: Fix Ajax system; the last remnants of the old API must be swept away
#1957590: Remove remaining procedural ajax command usages.
#1843220: Convert form AJAX to new AJAX API
Open Questions:
1) Most of what is left in ajax.inc is related to forms. Does it make sense to rip it out and stick it in form.inc so we can get rid of ajax.inc entirely?
2) There's a massive block of documentation at the top of ajax.inc that needs updating. If we get rid of ajax.inc, where does this go?
3) The old ajax.inc had defgroup docs for all of the ajax commands, which was nice...is there something comparable for all of the different ajax command classes?
