TYPO3 Core

In the issue #53459 the uninstall step for activated extension, when one uses the remove button (I mean the trashcan, not the uninstall button) is removed.
With this, dependency check for active extensions requiring the one to be removed alongside with flushing the system cache is removed. This leads to Fatal Errors in Backend.

In order to lower complexity we remove now the possibility to remove active extensions and remove all code depending on this particular function. This follows the removal of the uninstall check for extensions to be removed.

Here are the rules for removing extension from now on:
- active extensions need to be uninstalled, then removed (as two steps)
- inactive extensions can be removed

Patch set 2 for branch master of project Packages/TYPO3.CMS has been pushed to the review server.
It is available at https://review.typo3.org/29849