Add post processing hooks for Frontend Editing
In bug #16526, index_ts.php was rearranged to fix some frontend editing bugs. A side effect of this fix is that $TSFE->determineID() is no longer called after the frontend editing code runs.
While this was by no means documented or intended behavior, calling determineID() after frontend editing allowed content elements to be moved in TemplaVoila using earlier TYPO3 versions. TemplaVoila stores its content elements and their order in an XML structure within the page record so this page record must be updated after a content element is moved or hidden. If the record is not updated, the change will not appear until the entire page is refreshed. Among other things, the call to determineID() fetches a fresh copy of the page record.
The attached patch adds two hooks within frontend editing after any data changes are complete. It's up to third party extension (such as TemplaVoila and others) to implement these hooks and make sure they have fresh data but this at least opens up the possibility that they can work.
(issue imported from #M7607)